#include "cache.h" /* STATES AND TRANSITIONS * * entry | entry * v v * HOT -> DIRTY --> CLEAN --> EVICT * v | v * flush | evict * v | v * save | free * callback | callback * */ typedef int32_t REFCOUNT; #define REFCOUNT_DELETING (-100) // to use ARAL uncomment the following line: #define PGC_WITH_ARAL 1 typedef enum __attribute__ ((__packed__)) { // mutually exclusive flags PGC_PAGE_CLEAN = (1 << 0), // none of the following PGC_PAGE_DIRTY = (1 << 1), // contains unsaved data PGC_PAGE_HOT = (1 << 2), // currently being collected // flags related to various actions on each page PGC_PAGE_IS_BEING_DELETED = (1 << 3), PGC_PAGE_IS_BEING_MIGRATED_TO_V2 = (1 << 4), PGC_PAGE_HAS_NO_DATA_IGNORE_ACCESSES = (1 << 5), PGC_PAGE_HAS_BEEN_ACCESSED = (1 << 6), } PGC_PAGE_FLAGS; #define page_flag_check(page, flag) (__atomic_load_n(&((page)->flags), __ATOMIC_ACQUIRE) & (flag)) #define page_flag_set(page, flag) __atomic_or_fetch(&((page)->flags), flag, __ATOMIC_RELEASE) #define page_flag_clear(page, flag) __atomic_and_fetch(&((page)->flags), ~(flag), __ATOMIC_RELEASE) #define page_get_status_flags(page) page_flag_check(page, PGC_PAGE_HOT | PGC_PAGE_DIRTY | PGC_PAGE_CLEAN) #define is_page_hot(page) (page_get_status_flags(page) == PGC_PAGE_HOT) #define is_page_dirty(page) (page_get_status_flags(page) == PGC_PAGE_DIRTY) #define is_page_clean(page) (page_get_status_flags(page) == PGC_PAGE_CLEAN) struct pgc_page { // indexing data Word_t section; Word_t metric_id; time_t start_time_s; time_t end_time_s; uint32_t update_every_s; uint32_t assumed_size; REFCOUNT refcount; uint16_t accesses; // counts the number of accesses on this page PGC_PAGE_FLAGS flags; SPINLOCK transition_spinlock; // when the page changes between HOT, DIRTY, CLEAN, we have to get this lock struct { struct pgc_page *next; struct pgc_page *prev; } link; void *data; uint8_t custom_data[]; // IMPORTANT! // THIS STRUCTURE NEEDS TO BE INITIALIZED BY HAND! }; struct pgc_linked_list { SPINLOCK spinlock; union { PGC_PAGE *base; Pvoid_t sections_judy; }; PGC_PAGE_FLAGS flags; size_t version; size_t last_version_checked; bool linked_list_in_sections_judy; // when true, we use 'sections_judy', otherwise we use 'base' struct pgc_queue_statistics *stats; }; struct pgc { struct { char name[PGC_NAME_MAX + 1]; size_t partitions; size_t clean_size; size_t max_dirty_pages_per_call; size_t max_pages_per_inline_eviction; size_t max_skip_pages_per_inline_eviction; size_t max_flushes_inline; size_t max_workers_evict_inline; size_t additional_bytes_per_page; free_clean_page_callback pgc_free_clean_cb; save_dirty_page_callback pgc_save_dirty_cb; save_dirty_init_callback pgc_save_init_cb; PGC_OPTIONS options; size_t severe_pressure_per1000; size_t aggressive_evict_per1000; size_t healthy_size_per1000; size_t evict_low_threshold_per1000; dynamic_target_cache_size_callback dynamic_target_size_cb; } config; #ifdef PGC_WITH_ARAL ARAL **aral; #endif PGC_CACHE_LINE_PADDING(0); struct pgc_index { netdata_rwlock_t rwlock; Pvoid_t sections_judy; } *index; PGC_CACHE_LINE_PADDING(1); struct { SPINLOCK spinlock; size_t per1000; } usage; PGC_CACHE_LINE_PADDING(2); struct pgc_linked_list clean; // LRU is applied here to free memory from the cache PGC_CACHE_LINE_PADDING(3); struct pgc_linked_list dirty; // in the dirty list, pages are ordered the way they were marked dirty PGC_CACHE_LINE_PADDING(4); struct pgc_linked_list hot; // in the hot list, pages are order the way they were marked hot PGC_CACHE_LINE_PADDING(5); struct pgc_statistics stats; // statistics #ifdef NETDATA_PGC_POINTER_CHECK PGC_CACHE_LINE_PADDING(6); netdata_mutex_t global_pointer_registry_mutex; Pvoid_t global_pointer_registry; #endif }; // ---------------------------------------------------------------------------- // validate each pointer is indexed once - internal checks only static inline void pointer_index_init(PGC *cache __maybe_unused) { #ifdef NETDATA_PGC_POINTER_CHECK netdata_mutex_init(&cache->global_pointer_registry_mutex); #else ; #endif } static inline void pointer_destroy_index(PGC *cache __maybe_unused) { #ifdef NETDATA_PGC_POINTER_CHECK netdata_mutex_lock(&cache->global_pointer_registry_mutex); JudyHSFreeArray(&cache->global_pointer_registry, PJE0); netdata_mutex_unlock(&cache->global_pointer_registry_mutex); #else ; #endif } static inline void pointer_add(PGC *cache __maybe_unused, PGC_PAGE *page __maybe_unused) { #ifdef NETDATA_PGC_POINTER_CHECK netdata_mutex_lock(&cache->global_pointer_registry_mutex); Pvoid_t *PValue = JudyHSIns(&cache->global_pointer_registry, &page, sizeof(void *), PJE0); if(*PValue != NULL) fatal("pointer already exists in registry"); *PValue = page; netdata_mutex_unlock(&cache->global_pointer_registry_mutex); #else ; #endif } static inline void pointer_check(PGC *cache __maybe_unused, PGC_PAGE *page __maybe_unused) { #ifdef NETDATA_PGC_POINTER_CHECK netdata_mutex_lock(&cache->global_pointer_registry_mutex); Pvoid_t *PValue = JudyHSGet(cache->global_pointer_registry, &page, sizeof(void *)); if(PValue == NULL) fatal("pointer is not found in registry"); netdata_mutex_unlock(&cache->global_pointer_registry_mutex); #else ; #endif } static inline void pointer_del(PGC *cache __maybe_unused, PGC_PAGE *page __maybe_unused) { #ifdef NETDATA_PGC_POINTER_CHECK netdata_mutex_lock(&cache->global_pointer_registry_mutex); int ret = JudyHSDel(&cache->global_pointer_registry, &page, sizeof(void *), PJE0); if(!ret) fatal("pointer to be deleted does not exist in registry"); netdata_mutex_unlock(&cache->global_pointer_registry_mutex); #else ; #endif } // ---------------------------------------------------------------------------- // locking static inline size_t pgc_indexing_partition(PGC *cache, Word_t metric_id) { static __thread Word_t last_metric_id = 0; static __thread size_t last_partition = 0; if(metric_id == last_metric_id || cache->config.partitions == 1) return last_partition; last_metric_id = metric_id; last_partition = indexing_partition(metric_id, cache->config.partitions); return last_partition; } static inline void pgc_index_read_lock(PGC *cache, size_t partition) { netdata_rwlock_rdlock(&cache->index[partition].rwlock); } static inline void pgc_index_read_unlock(PGC *cache, size_t partition) { netdata_rwlock_unlock(&cache->index[partition].rwlock); } //static inline bool pgc_index_write_trylock(PGC *cache, size_t partition) { // return !netdata_rwlock_trywrlock(&cache->index[partition].rwlock); //} static inline void pgc_index_write_lock(PGC *cache, size_t partition) { netdata_rwlock_wrlock(&cache->index[partition].rwlock); } static inline void pgc_index_write_unlock(PGC *cache, size_t partition) { netdata_rwlock_unlock(&cache->index[partition].rwlock); } static inline bool pgc_ll_trylock(PGC *cache __maybe_unused, struct pgc_linked_list *ll) { return netdata_spinlock_trylock(&ll->spinlock); } static inline void pgc_ll_lock(PGC *cache __maybe_unused, struct pgc_linked_list *ll) { netdata_spinlock_lock(&ll->spinlock); } static inline void pgc_ll_unlock(PGC *cache __maybe_unused, struct pgc_linked_list *ll) { netdata_spinlock_unlock(&ll->spinlock); } static inline bool page_transition_trylock(PGC *cache __maybe_unused, PGC_PAGE *page) { return netdata_spinlock_trylock(&page->transition_spinlock); } static inline void page_transition_lock(PGC *cache __maybe_unused, PGC_PAGE *page) { netdata_spinlock_lock(&page->transition_spinlock); } static inline void page_transition_unlock(PGC *cache __maybe_unused, PGC_PAGE *page) { netdata_spinlock_unlock(&page->transition_spinlock); } // ---------------------------------------------------------------------------- // evictions control static inline size_t cache_usage_per1000(PGC *cache, size_t *size_to_evict) { if(size_to_evict) netdata_spinlock_lock(&cache->usage.spinlock); else if(!netdata_spinlock_trylock(&cache->usage.spinlock)) return __atomic_load_n(&cache->usage.per1000, __ATOMIC_RELAXED); size_t current_cache_size; size_t wanted_cache_size; size_t per1000; size_t dirty = __atomic_load_n(&cache->dirty.stats->size, __ATOMIC_RELAXED); size_t hot = __atomic_load_n(&cache->hot.stats->size, __ATOMIC_RELAXED); if(cache->config.options & PGC_OPTIONS_AUTOSCALE) { size_t dirty_max = __atomic_load_n(&cache->dirty.stats->max_size, __ATOMIC_RELAXED); size_t hot_max = __atomic_load_n(&cache->hot.stats->max_size, __ATOMIC_RELAXED); // our promise to users size_t max_size1 = MAX(hot_max, hot) * 2; // protection against slow flushing size_t max_size2 = hot_max + ((dirty_max < hot_max / 2) ? hot_max / 2 : dirty_max * 2); // the final wanted cache size wanted_cache_size = MIN(max_size1, max_size2); if(cache->config.dynamic_target_size_cb) { size_t wanted_cache_size_cb = cache->config.dynamic_target_size_cb(); if(wanted_cache_size_cb > wanted_cache_size) wanted_cache_size = wanted_cache_size_cb; } if (wanted_cache_size < hot + dirty + cache->config.clean_size) wanted_cache_size = hot + dirty + cache->config.clean_size; } else wanted_cache_size = hot + dirty + cache->config.clean_size; // protection again huge queries // if huge queries are running, or huge amounts need to be saved // allow the cache to grow more (hot pages in main cache are also referenced) size_t referenced_size = __atomic_load_n(&cache->stats.referenced_size, __ATOMIC_RELAXED); if(unlikely(wanted_cache_size < referenced_size * 2 / 3)) wanted_cache_size = referenced_size * 2 / 3; current_cache_size = __atomic_load_n(&cache->stats.size, __ATOMIC_RELAXED); // + pgc_aral_overhead(); per1000 = (size_t)((unsigned long long)current_cache_size * 1000ULL / (unsigned long long)wanted_cache_size); __atomic_store_n(&cache->usage.per1000, per1000, __ATOMIC_RELAXED); __atomic_store_n(&cache->stats.wanted_cache_size, wanted_cache_size, __ATOMIC_RELAXED); __atomic_store_n(&cache->stats.current_cache_size, current_cache_size, __ATOMIC_RELAXED); netdata_spinlock_unlock(&cache->usage.spinlock); if(size_to_evict) { size_t target = (size_t)((unsigned long long)wanted_cache_size * (unsigned long long)cache->config.evict_low_threshold_per1000 / 1000ULL); if(current_cache_size > target) *size_to_evict = current_cache_size - target; else *size_to_evict = 0; } if(per1000 >= cache->config.severe_pressure_per1000) __atomic_add_fetch(&cache->stats.events_cache_under_severe_pressure, 1, __ATOMIC_RELAXED); else if(per1000 >= cache->config.aggressive_evict_per1000) __atomic_add_fetch(&cache->stats.events_cache_needs_space_aggressively, 1, __ATOMIC_RELAXED); return per1000; } static inline bool cache_pressure(PGC *cache, size_t limit) { return (cache_usage_per1000(cache, NULL) >= limit); } #define cache_under_severe_pressure(cache) cache_pressure(cache, (cache)->config.severe_pressure_per1000) #define cache_needs_space_aggressively(cache) cache_pressure(cache, (cache)->config.aggressive_evict_per1000) #define cache_above_healthy_limit(cache) cache_pressure(cache, (cache)->config.healthy_size_per1000) typedef bool (*evict_filter)(PGC_PAGE *page, void *data); static bool evict_pages_with_filter(PGC *cache, size_t max_skip, size_t max_evict, bool wait, bool all_of_them, evict_filter filter, void *data); #define evict_pages(cache, max_skip, max_evict, wait, all_of_them) evict_pages_with_filter(cache, max_skip, max_evict, wait, all_of_them, NULL, NULL) static inline void evict_on_clean_page_added(PGC *cache __maybe_unused) { if((cache->config.options & PGC_OPTIONS_EVICT_PAGES_INLINE) || cache_needs_space_aggressively(cache)) { evict_pages(cache, cache->config.max_skip_pages_per_inline_eviction, cache->config.max_pages_per_inline_eviction, false, false); } } static inline void evict_on_page_release_when_permitted(PGC *cache __maybe_unused) { if ((cache->config.options & PGC_OPTIONS_EVICT_PAGES_INLINE) || cache_under_severe_pressure(cache)) { evict_pages(cache, cache->config.max_skip_pages_per_inline_eviction, cache->config.max_pages_per_inline_eviction, false, false); } } // ---------------------------------------------------------------------------- // flushing control static bool flush_pages(PGC *cache, size_t max_flushes, Word_t section, bool wait, bool all_of_them); static inline bool flushing_critical(PGC *cache) { if(unlikely(__atomic_load_n(&cache->dirty.stats->size, __ATOMIC_RELAXED) > __atomic_load_n(&cache->hot.stats->max_size, __ATOMIC_RELAXED))) { __atomic_add_fetch(&cache->stats.events_flush_critical, 1, __ATOMIC_RELAXED); return true; } return false; } // ---------------------------------------------------------------------------- // helpers static inline size_t page_assumed_size(PGC *cache, size_t size) { return size + (sizeof(PGC_PAGE) + cache->config.additional_bytes_per_page + sizeof(Word_t) * 3); } static inline size_t page_size_from_assumed_size(PGC *cache, size_t assumed_size) { return assumed_size - (sizeof(PGC_PAGE) + cache->config.additional_bytes_per_page + sizeof(Word_t) * 3); } // ---------------------------------------------------------------------------- // Linked list management static inline void atomic_set_max(size_t *max, size_t desired) { size_t expected; expected = __atomic_load_n(max, __ATOMIC_RELAXED); do { if(expected >= desired) return; } while(!__atomic_compare_exchange_n(max, &expected, desired, false, __ATOMIC_RELAXED, __ATOMIC_RELAXED)); } struct section_pages { SPINLOCK migration_to_v2_spinlock; size_t entries; size_t size; PGC_PAGE *base; }; static ARAL *pgc_section_pages_aral = NULL; static void pgc_section_pages_static_aral_init(void) { static SPINLOCK spinlock = NETDATA_SPINLOCK_INITIALIZER; if(unlikely(!pgc_section_pages_aral)) { netdata_spinlock_lock(&spinlock); // we have to check again if(!pgc_section_pages_aral) pgc_section_pages_aral = aral_create( "pgc_section", sizeof(struct section_pages), 0, 65536, NULL, NULL, NULL, false, false); netdata_spinlock_unlock(&spinlock); } } static inline void pgc_stats_ll_judy_change(PGC *cache, struct pgc_linked_list *ll, size_t mem_before_judyl, size_t mem_after_judyl) { if(mem_after_judyl > mem_before_judyl) { __atomic_add_fetch(&ll->stats->size, mem_after_judyl - mem_before_judyl, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.size, mem_after_judyl - mem_before_judyl, __ATOMIC_RELAXED); } else if(mem_after_judyl < mem_before_judyl) { __atomic_sub_fetch(&ll->stats->size, mem_before_judyl - mem_after_judyl, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.size, mem_before_judyl - mem_after_judyl, __ATOMIC_RELAXED); } } static inline void pgc_stats_index_judy_change(PGC *cache, size_t mem_before_judyl, size_t mem_after_judyl) { if(mem_after_judyl > mem_before_judyl) { __atomic_add_fetch(&cache->stats.size, mem_after_judyl - mem_before_judyl, __ATOMIC_RELAXED); } else if(mem_after_judyl < mem_before_judyl) { __atomic_sub_fetch(&cache->stats.size, mem_before_judyl - mem_after_judyl, __ATOMIC_RELAXED); } } static void pgc_ll_add(PGC *cache __maybe_unused, struct pgc_linked_list *ll, PGC_PAGE *page, bool having_lock) { if(!having_lock) pgc_ll_lock(cache, ll); internal_fatal(page_get_status_flags(page) != 0, "DBENGINE CACHE: invalid page flags, the page has %d, but it is should be %d", page_get_status_flags(page), 0); if(ll->linked_list_in_sections_judy) { size_t mem_before_judyl, mem_after_judyl; mem_before_judyl = JudyLMemUsed(ll->sections_judy); Pvoid_t *section_pages_pptr = JudyLIns(&ll->sections_judy, page->section, PJE0); mem_after_judyl = JudyLMemUsed(ll->sections_judy); struct section_pages *sp = *section_pages_pptr; if(!sp) { // sp = callocz(1, sizeof(struct section_pages)); sp = aral_mallocz(pgc_section_pages_aral); memset(sp, 0, sizeof(struct section_pages)); *section_pages_pptr = sp; mem_after_judyl += sizeof(struct section_pages); } pgc_stats_ll_judy_change(cache, ll, mem_before_judyl, mem_after_judyl); sp->entries++; sp->size += page->assumed_size; DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(sp->base, page, link.prev, link.next); if((sp->entries % cache->config.max_dirty_pages_per_call) == 0) ll->version++; } else { // CLEAN pages end up here. // - New pages created as CLEAN, always have 1 access. // - DIRTY pages made CLEAN, depending on their accesses may be appended (accesses > 0) or prepended (accesses = 0). if(page->accesses || page_flag_check(page, PGC_PAGE_HAS_BEEN_ACCESSED | PGC_PAGE_HAS_NO_DATA_IGNORE_ACCESSES) == PGC_PAGE_HAS_BEEN_ACCESSED) { DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(ll->base, page, link.prev, link.next); page_flag_clear(page, PGC_PAGE_HAS_BEEN_ACCESSED); } else DOUBLE_LINKED_LIST_PREPEND_ITEM_UNSAFE(ll->base, page, link.prev, link.next); ll->version++; } page_flag_set(page, ll->flags); if(!having_lock) pgc_ll_unlock(cache, ll); size_t entries = __atomic_add_fetch(&ll->stats->entries, 1, __ATOMIC_RELAXED); size_t size = __atomic_add_fetch(&ll->stats->size, page->assumed_size, __ATOMIC_RELAXED); __atomic_add_fetch(&ll->stats->added_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&ll->stats->added_size, page->assumed_size, __ATOMIC_RELAXED); atomic_set_max(&ll->stats->max_entries, entries); atomic_set_max(&ll->stats->max_size, size); } static void pgc_ll_del(PGC *cache __maybe_unused, struct pgc_linked_list *ll, PGC_PAGE *page, bool having_lock) { __atomic_sub_fetch(&ll->stats->entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&ll->stats->size, page->assumed_size, __ATOMIC_RELAXED); __atomic_add_fetch(&ll->stats->removed_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&ll->stats->removed_size, page->assumed_size, __ATOMIC_RELAXED); if(!having_lock) pgc_ll_lock(cache, ll); internal_fatal(page_get_status_flags(page) != ll->flags, "DBENGINE CACHE: invalid page flags, the page has %d, but it is should be %d", page_get_status_flags(page), ll->flags); page_flag_clear(page, ll->flags); if(ll->linked_list_in_sections_judy) { Pvoid_t *section_pages_pptr = JudyLGet(ll->sections_judy, page->section, PJE0); internal_fatal(!section_pages_pptr, "DBENGINE CACHE: page should be in Judy LL, but it is not"); struct section_pages *sp = *section_pages_pptr; sp->entries--; sp->size -= page->assumed_size; DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(sp->base, page, link.prev, link.next); if(!sp->base) { size_t mem_before_judyl, mem_after_judyl; mem_before_judyl = JudyLMemUsed(ll->sections_judy); int rc = JudyLDel(&ll->sections_judy, page->section, PJE0); mem_after_judyl = JudyLMemUsed(ll->sections_judy); if(!rc) fatal("DBENGINE CACHE: cannot delete section from Judy LL"); // freez(sp); aral_freez(pgc_section_pages_aral, sp); mem_after_judyl -= sizeof(struct section_pages); pgc_stats_ll_judy_change(cache, ll, mem_before_judyl, mem_after_judyl); } } else { DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(ll->base, page, link.prev, link.next); ll->version++; } if(!having_lock) pgc_ll_unlock(cache, ll); } static inline void page_has_been_accessed(PGC *cache, PGC_PAGE *page) { PGC_PAGE_FLAGS flags = page_flag_check(page, PGC_PAGE_CLEAN | PGC_PAGE_HAS_NO_DATA_IGNORE_ACCESSES); if (!(flags & PGC_PAGE_HAS_NO_DATA_IGNORE_ACCESSES)) { __atomic_add_fetch(&page->accesses, 1, __ATOMIC_RELAXED); if (flags & PGC_PAGE_CLEAN) { if(pgc_ll_trylock(cache, &cache->clean)) { DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(cache->clean.base, page, link.prev, link.next); DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(cache->clean.base, page, link.prev, link.next); pgc_ll_unlock(cache, &cache->clean); page_flag_clear(page, PGC_PAGE_HAS_BEEN_ACCESSED); } else page_flag_set(page, PGC_PAGE_HAS_BEEN_ACCESSED); } } } // ---------------------------------------------------------------------------- // state transitions static inline void page_set_clean(PGC *cache, PGC_PAGE *page, bool having_transition_lock, bool having_clean_lock) { if(!having_transition_lock) page_transition_lock(cache, page); PGC_PAGE_FLAGS flags = page_get_status_flags(page); if(flags & PGC_PAGE_CLEAN) { if(!having_transition_lock) page_transition_unlock(cache, page); return; } if(flags & PGC_PAGE_HOT) pgc_ll_del(cache, &cache->hot, page, false); if(flags & PGC_PAGE_DIRTY) pgc_ll_del(cache, &cache->dirty, page, false); // first add to linked list, the set the flag (required for move_page_last()) pgc_ll_add(cache, &cache->clean, page, having_clean_lock); if(!having_transition_lock) page_transition_unlock(cache, page); } static inline void page_set_dirty(PGC *cache, PGC_PAGE *page, bool having_hot_lock) { if(!having_hot_lock) // to avoid deadlocks, we have to get the hot lock before the page transition // since this is what all_hot_to_dirty() does pgc_ll_lock(cache, &cache->hot); page_transition_lock(cache, page); PGC_PAGE_FLAGS flags = page_get_status_flags(page); if(flags & PGC_PAGE_DIRTY) { page_transition_unlock(cache, page); if(!having_hot_lock) // we don't need the hot lock anymore pgc_ll_unlock(cache, &cache->hot); return; } __atomic_add_fetch(&cache->stats.hot2dirty_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.hot2dirty_size, page->assumed_size, __ATOMIC_RELAXED); if(likely(flags & PGC_PAGE_HOT)) pgc_ll_del(cache, &cache->hot, page, true); if(!having_hot_lock) // we don't need the hot lock anymore pgc_ll_unlock(cache, &cache->hot); if(unlikely(flags & PGC_PAGE_CLEAN)) pgc_ll_del(cache, &cache->clean, page, false); // first add to linked list, the set the flag (required for move_page_last()) pgc_ll_add(cache, &cache->dirty, page, false); __atomic_sub_fetch(&cache->stats.hot2dirty_entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.hot2dirty_size, page->assumed_size, __ATOMIC_RELAXED); page_transition_unlock(cache, page); } static inline void page_set_hot(PGC *cache, PGC_PAGE *page) { page_transition_lock(cache, page); PGC_PAGE_FLAGS flags = page_get_status_flags(page); if(flags & PGC_PAGE_HOT) { page_transition_unlock(cache, page); return; } if(flags & PGC_PAGE_DIRTY) pgc_ll_del(cache, &cache->dirty, page, false); if(flags & PGC_PAGE_CLEAN) pgc_ll_del(cache, &cache->clean, page, false); // first add to linked list, the set the flag (required for move_page_last()) pgc_ll_add(cache, &cache->hot, page, false); page_transition_unlock(cache, page); } // ---------------------------------------------------------------------------- // Referencing static inline size_t PGC_REFERENCED_PAGES(PGC *cache) { return __atomic_load_n(&cache->stats.referenced_entries, __ATOMIC_RELAXED); } static inline void PGC_REFERENCED_PAGES_PLUS1(PGC *cache, PGC_PAGE *page) { __atomic_add_fetch(&cache->stats.referenced_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.referenced_size, page->assumed_size, __ATOMIC_RELAXED); } static inline void PGC_REFERENCED_PAGES_MINUS1(PGC *cache, size_t assumed_size) { __atomic_sub_fetch(&cache->stats.referenced_entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.referenced_size, assumed_size, __ATOMIC_RELAXED); } // If the page is not already acquired, // YOU HAVE TO HAVE THE QUEUE (hot, dirty, clean) THE PAGE IS IN, L O C K E D ! // If you don't have it locked, NOTHING PREVENTS THIS PAGE FOR VANISHING WHILE THIS IS CALLED! static inline bool page_acquire(PGC *cache, PGC_PAGE *page) { __atomic_add_fetch(&cache->stats.acquires, 1, __ATOMIC_RELAXED); REFCOUNT expected, desired; expected = __atomic_load_n(&page->refcount, __ATOMIC_RELAXED); size_t spins = 0; do { spins++; if(unlikely(expected < 0)) return false; desired = expected + 1; } while(!__atomic_compare_exchange_n(&page->refcount, &expected, desired, false, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED)); if(unlikely(spins > 1)) __atomic_add_fetch(&cache->stats.acquire_spins, spins - 1, __ATOMIC_RELAXED); if(desired == 1) PGC_REFERENCED_PAGES_PLUS1(cache, page); return true; } static inline void page_release(PGC *cache, PGC_PAGE *page, bool evict_if_necessary) { __atomic_add_fetch(&cache->stats.releases, 1, __ATOMIC_RELAXED); size_t assumed_size = page->assumed_size; // take the size before we release it REFCOUNT expected, desired; expected = __atomic_load_n(&page->refcount, __ATOMIC_RELAXED); size_t spins = 0; do { spins++; internal_fatal(expected <= 0, "DBENGINE CACHE: trying to release a page with reference counter %d", expected); desired = expected - 1; } while(!__atomic_compare_exchange_n(&page->refcount, &expected, desired, false, __ATOMIC_RELEASE, __ATOMIC_RELAXED)); if(unlikely(spins > 1)) __atomic_add_fetch(&cache->stats.release_spins, spins - 1, __ATOMIC_RELAXED); if(desired == 0) { PGC_REFERENCED_PAGES_MINUS1(cache, assumed_size); if(evict_if_necessary) evict_on_page_release_when_permitted(cache); } } static inline bool non_acquired_page_get_for_deletion___while_having_clean_locked(PGC *cache __maybe_unused, PGC_PAGE *page) { __atomic_add_fetch(&cache->stats.acquires_for_deletion, 1, __ATOMIC_RELAXED); internal_fatal(!is_page_clean(page), "DBENGINE CACHE: only clean pages can be deleted"); REFCOUNT expected, desired; expected = __atomic_load_n(&page->refcount, __ATOMIC_RELAXED); size_t spins = 0; bool delete_it; do { spins++; if (expected == 0) { desired = REFCOUNT_DELETING; delete_it = true; } else { delete_it = false; break; } } while(!__atomic_compare_exchange_n(&page->refcount, &expected, desired, false, __ATOMIC_RELEASE, __ATOMIC_RELAXED)); if(delete_it) { // we can delete this page internal_fatal(page_flag_check(page, PGC_PAGE_IS_BEING_DELETED), "DBENGINE CACHE: page is already being deleted"); page_flag_set(page, PGC_PAGE_IS_BEING_DELETED); } if(unlikely(spins > 1)) __atomic_add_fetch(&cache->stats.delete_spins, spins - 1, __ATOMIC_RELAXED); return delete_it; } static inline bool acquired_page_get_for_deletion_or_release_it(PGC *cache __maybe_unused, PGC_PAGE *page) { __atomic_add_fetch(&cache->stats.acquires_for_deletion, 1, __ATOMIC_RELAXED); size_t assumed_size = page->assumed_size; // take the size before we release it REFCOUNT expected, desired; expected = __atomic_load_n(&page->refcount, __ATOMIC_RELAXED); size_t spins = 0; bool delete_it; do { spins++; internal_fatal(expected < 1, "DBENGINE CACHE: page to be deleted should be acquired by the caller."); if (expected == 1) { // we are the only one having this page referenced desired = REFCOUNT_DELETING; delete_it = true; } else { // this page cannot be deleted desired = expected - 1; delete_it = false; } } while(!__atomic_compare_exchange_n(&page->refcount, &expected, desired, false, __ATOMIC_RELEASE, __ATOMIC_RELAXED)); if(delete_it) { PGC_REFERENCED_PAGES_MINUS1(cache, assumed_size); // we can delete this page internal_fatal(page_flag_check(page, PGC_PAGE_IS_BEING_DELETED), "DBENGINE CACHE: page is already being deleted"); page_flag_set(page, PGC_PAGE_IS_BEING_DELETED); } if(unlikely(spins > 1)) __atomic_add_fetch(&cache->stats.delete_spins, spins - 1, __ATOMIC_RELAXED); return delete_it; } // ---------------------------------------------------------------------------- // Indexing static inline void free_this_page(PGC *cache, PGC_PAGE *page, size_t partition __maybe_unused) { // call the callback to free the user supplied memory cache->config.pgc_free_clean_cb(cache, (PGC_ENTRY){ .section = page->section, .metric_id = page->metric_id, .start_time_s = page->start_time_s, .end_time_s = __atomic_load_n(&page->end_time_s, __ATOMIC_RELAXED), .update_every_s = page->update_every_s, .size = page_size_from_assumed_size(cache, page->assumed_size), .hot = (is_page_hot(page)) ? true : false, .data = page->data, .custom_data = (cache->config.additional_bytes_per_page) ? page->custom_data : NULL, }); // update statistics __atomic_add_fetch(&cache->stats.removed_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.removed_size, page->assumed_size, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.size, page->assumed_size, __ATOMIC_RELAXED); // free our memory #ifdef PGC_WITH_ARAL aral_freez(cache->aral[partition], page); #else freez(page); #endif } static void remove_this_page_from_index_unsafe(PGC *cache, PGC_PAGE *page, size_t partition) { // remove it from the Judy arrays pointer_check(cache, page); internal_fatal(page_flag_check(page, PGC_PAGE_HOT | PGC_PAGE_DIRTY | PGC_PAGE_CLEAN), "DBENGINE CACHE: page to be removed from the cache is still in the linked-list"); internal_fatal(!page_flag_check(page, PGC_PAGE_IS_BEING_DELETED), "DBENGINE CACHE: page to be removed from the index, is not marked for deletion"); internal_fatal(partition != pgc_indexing_partition(cache, page->metric_id), "DBENGINE CACHE: attempted to remove this page from the wrong partition of the cache"); Pvoid_t *metrics_judy_pptr = JudyLGet(cache->index[partition].sections_judy, page->section, PJE0); if(unlikely(!metrics_judy_pptr)) fatal("DBENGINE CACHE: section '%lu' should exist, but it does not.", page->section); Pvoid_t *pages_judy_pptr = JudyLGet(*metrics_judy_pptr, page->metric_id, PJE0); if(unlikely(!pages_judy_pptr)) fatal("DBENGINE CACHE: metric '%lu' in section '%lu' should exist, but it does not.", page->metric_id, page->section); Pvoid_t *page_ptr = JudyLGet(*pages_judy_pptr, page->start_time_s, PJE0); if(unlikely(!page_ptr)) fatal("DBENGINE CACHE: page with start time '%ld' of metric '%lu' in section '%lu' should exist, but it does not.", page->start_time_s, page->metric_id, page->section); PGC_PAGE *found_page = *page_ptr; if(unlikely(found_page != page)) fatal("DBENGINE CACHE: page with start time '%ld' of metric '%lu' in section '%lu' should exist, but the index returned a different address.", page->start_time_s, page->metric_id, page->section); size_t mem_before_judyl = 0, mem_after_judyl = 0; mem_before_judyl += JudyLMemUsed(*pages_judy_pptr); if(unlikely(!JudyLDel(pages_judy_pptr, page->start_time_s, PJE0))) fatal("DBENGINE CACHE: page with start time '%ld' of metric '%lu' in section '%lu' exists, but cannot be deleted.", page->start_time_s, page->metric_id, page->section); mem_after_judyl += JudyLMemUsed(*pages_judy_pptr); mem_before_judyl += JudyLMemUsed(*metrics_judy_pptr); if(!*pages_judy_pptr && !JudyLDel(metrics_judy_pptr, page->metric_id, PJE0)) fatal("DBENGINE CACHE: metric '%lu' in section '%lu' exists and is empty, but cannot be deleted.", page->metric_id, page->section); mem_after_judyl += JudyLMemUsed(*metrics_judy_pptr); mem_before_judyl += JudyLMemUsed(cache->index[partition].sections_judy); if(!*metrics_judy_pptr && !JudyLDel(&cache->index[partition].sections_judy, page->section, PJE0)) fatal("DBENGINE CACHE: section '%lu' exists and is empty, but cannot be deleted.", page->section); mem_after_judyl += JudyLMemUsed(cache->index[partition].sections_judy); pgc_stats_index_judy_change(cache, mem_before_judyl, mem_after_judyl); pointer_del(cache, page); } static inline void remove_and_free_page_not_in_any_queue_and_acquired_for_deletion(PGC *cache, PGC_PAGE *page) { size_t partition = pgc_indexing_partition(cache, page->metric_id); pgc_index_write_lock(cache, partition); remove_this_page_from_index_unsafe(cache, page, partition); pgc_index_write_unlock(cache, partition); free_this_page(cache, page, partition); } static inline bool make_acquired_page_clean_and_evict_or_page_release(PGC *cache, PGC_PAGE *page) { pointer_check(cache, page); page_transition_lock(cache, page); pgc_ll_lock(cache, &cache->clean); // make it clean - it does not have any accesses, so it will be prepended page_set_clean(cache, page, true, true); if(!acquired_page_get_for_deletion_or_release_it(cache, page)) { pgc_ll_unlock(cache, &cache->clean); page_transition_unlock(cache, page); return false; } // remove it from the linked list pgc_ll_del(cache, &cache->clean, page, true); pgc_ll_unlock(cache, &cache->clean); page_transition_unlock(cache, page); remove_and_free_page_not_in_any_queue_and_acquired_for_deletion(cache, page); return true; } // returns true, when there is more work to do static bool evict_pages_with_filter(PGC *cache, size_t max_skip, size_t max_evict, bool wait, bool all_of_them, evict_filter filter, void *data) { size_t per1000 = cache_usage_per1000(cache, NULL); if(!all_of_them && per1000 < cache->config.healthy_size_per1000) // don't bother - not enough to do anything return false; size_t workers_running = __atomic_add_fetch(&cache->stats.workers_evict, 1, __ATOMIC_RELAXED); if(!wait && !all_of_them && workers_running > cache->config.max_workers_evict_inline && per1000 < cache->config.severe_pressure_per1000) { __atomic_sub_fetch(&cache->stats.workers_evict, 1, __ATOMIC_RELAXED); return false; } internal_fatal(cache->clean.linked_list_in_sections_judy, "wrong clean pages configuration - clean pages need to have a linked list, not a judy array"); if(unlikely(!max_skip)) max_skip = SIZE_MAX; else if(unlikely(max_skip < 2)) max_skip = 2; if(unlikely(!max_evict)) max_evict = SIZE_MAX; else if(unlikely(max_evict < 2)) max_evict = 2; size_t total_pages_evicted = 0; size_t total_pages_skipped = 0; bool stopped_before_finishing = false; size_t spins = 0; do { if(++spins > 1) __atomic_add_fetch(&cache->stats.evict_spins, 1, __ATOMIC_RELAXED); bool batch; size_t max_size_to_evict = 0; if (unlikely(all_of_them)) { max_size_to_evict = SIZE_MAX; batch = true; } else if(unlikely(wait)) { per1000 = cache_usage_per1000(cache, &max_size_to_evict); batch = (wait && per1000 > cache->config.severe_pressure_per1000) ? true : false; } else { batch = false; max_size_to_evict = (cache_above_healthy_limit(cache)) ? 1 : 0; } if (!max_size_to_evict) break; // check if we have to stop if(total_pages_evicted >= max_evict && !all_of_them) { stopped_before_finishing = true; break; } if(!all_of_them && !wait) { if(!pgc_ll_trylock(cache, &cache->clean)) { stopped_before_finishing = true; goto premature_exit; } // at this point we have the clean lock } else pgc_ll_lock(cache, &cache->clean); // find a page to evict PGC_PAGE *pages_to_evict = NULL; size_t pages_to_evict_size = 0; for(PGC_PAGE *page = cache->clean.base, *next = NULL, *first_page_we_relocated = NULL; page ; page = next) { next = page->link.next; if(unlikely(page == first_page_we_relocated)) // we did a complete loop on all pages break; if(unlikely(page_flag_check(page, PGC_PAGE_HAS_BEEN_ACCESSED | PGC_PAGE_HAS_NO_DATA_IGNORE_ACCESSES) == PGC_PAGE_HAS_BEEN_ACCESSED)) { DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(cache->clean.base, page, link.prev, link.next); DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(cache->clean.base, page, link.prev, link.next); page_flag_clear(page, PGC_PAGE_HAS_BEEN_ACCESSED); continue; } if(unlikely(filter && !filter(page, data))) continue; if(non_acquired_page_get_for_deletion___while_having_clean_locked(cache, page)) { // we can delete this page // remove it from the clean list pgc_ll_del(cache, &cache->clean, page, true); __atomic_add_fetch(&cache->stats.evicting_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.evicting_size, page->assumed_size, __ATOMIC_RELAXED); DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(pages_to_evict, page, link.prev, link.next); pages_to_evict_size += page->assumed_size; if(unlikely(all_of_them || (batch && pages_to_evict_size < max_size_to_evict))) // get more pages ; else // one page at a time break; } else { // we can't delete this page if(!first_page_we_relocated) first_page_we_relocated = page; DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(cache->clean.base, page, link.prev, link.next); DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(cache->clean.base, page, link.prev, link.next); // check if we have to stop if(unlikely(++total_pages_skipped >= max_skip && !all_of_them)) { stopped_before_finishing = true; break; } } } pgc_ll_unlock(cache, &cache->clean); if(likely(pages_to_evict)) { // remove them from the index if(unlikely(pages_to_evict->link.next)) { // we have many pages, let's minimize the index locks we are going to get PGC_PAGE *pages_per_partition[cache->config.partitions]; memset(pages_per_partition, 0, sizeof(PGC_PAGE *) * cache->config.partitions); // sort them by partition for (PGC_PAGE *page = pages_to_evict, *next = NULL; page; page = next) { next = page->link.next; size_t partition = pgc_indexing_partition(cache, page->metric_id); DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(pages_to_evict, page, link.prev, link.next); DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(pages_per_partition[partition], page, link.prev, link.next); } // remove them from the index for (size_t partition = 0; partition < cache->config.partitions; partition++) { if (!pages_per_partition[partition]) continue; pgc_index_write_lock(cache, partition); for (PGC_PAGE *page = pages_per_partition[partition]; page; page = page->link.next) remove_this_page_from_index_unsafe(cache, page, partition); pgc_index_write_unlock(cache, partition); } // free them for (size_t partition = 0; partition < cache->config.partitions; partition++) { if (!pages_per_partition[partition]) continue; for (PGC_PAGE *page = pages_per_partition[partition], *next = NULL; page; page = next) { next = page->link.next; size_t page_size = page->assumed_size; free_this_page(cache, page, partition); __atomic_sub_fetch(&cache->stats.evicting_entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.evicting_size, page_size, __ATOMIC_RELAXED); total_pages_evicted++; } } } else { // just one page to be evicted PGC_PAGE *page = pages_to_evict; size_t page_size = page->assumed_size; size_t partition = pgc_indexing_partition(cache, page->metric_id); pgc_index_write_lock(cache, partition); remove_this_page_from_index_unsafe(cache, page, partition); pgc_index_write_unlock(cache, partition); free_this_page(cache, page, partition); __atomic_sub_fetch(&cache->stats.evicting_entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.evicting_size, page_size, __ATOMIC_RELAXED); total_pages_evicted++; } } else break; } while(all_of_them || (total_pages_evicted < max_evict && total_pages_skipped < max_skip)); if(all_of_them && !filter) { pgc_ll_lock(cache, &cache->clean); if(cache->clean.stats->entries) { error_limit_static_global_var(erl, 1, 0); error_limit(&erl, "DBENGINE CACHE: cannot free all clean pages, %zu are still in the clean queue", cache->clean.stats->entries); } pgc_ll_unlock(cache, &cache->clean); } premature_exit: if(unlikely(total_pages_skipped)) __atomic_add_fetch(&cache->stats.evict_skipped, total_pages_skipped, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.workers_evict, 1, __ATOMIC_RELAXED); return stopped_before_finishing; } static PGC_PAGE *page_add(PGC *cache, PGC_ENTRY *entry, bool *added) { __atomic_add_fetch(&cache->stats.workers_add, 1, __ATOMIC_RELAXED); size_t partition = pgc_indexing_partition(cache, entry->metric_id); #ifdef PGC_WITH_ARAL PGC_PAGE *allocation = aral_mallocz(cache->aral[partition]); #endif PGC_PAGE *page; size_t spins = 0; do { if(++spins > 1) __atomic_add_fetch(&cache->stats.insert_spins, 1, __ATOMIC_RELAXED); pgc_index_write_lock(cache, partition); size_t mem_before_judyl = 0, mem_after_judyl = 0; mem_before_judyl += JudyLMemUsed(cache->index[partition].sections_judy); Pvoid_t *metrics_judy_pptr = JudyLIns(&cache->index[partition].sections_judy, entry->section, PJE0); if(unlikely(!metrics_judy_pptr || metrics_judy_pptr == PJERR)) fatal("DBENGINE CACHE: corrupted sections judy array"); mem_after_judyl += JudyLMemUsed(cache->index[partition].sections_judy); mem_before_judyl += JudyLMemUsed(*metrics_judy_pptr); Pvoid_t *pages_judy_pptr = JudyLIns(metrics_judy_pptr, entry->metric_id, PJE0); if(unlikely(!pages_judy_pptr || pages_judy_pptr == PJERR)) fatal("DBENGINE CACHE: corrupted pages judy array"); mem_after_judyl += JudyLMemUsed(*metrics_judy_pptr); mem_before_judyl += JudyLMemUsed(*pages_judy_pptr); Pvoid_t *page_ptr = JudyLIns(pages_judy_pptr, entry->start_time_s, PJE0); if(unlikely(!page_ptr || page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in judy array"); mem_after_judyl += JudyLMemUsed(*pages_judy_pptr); pgc_stats_index_judy_change(cache, mem_before_judyl, mem_after_judyl); page = *page_ptr; if (likely(!page)) { #ifdef PGC_WITH_ARAL page = allocation; allocation = NULL; #else page = mallocz(sizeof(PGC_PAGE) + cache->config.additional_bytes_per_page); #endif page->refcount = 1; page->accesses = (entry->hot) ? 0 : 1; page->flags = 0; page->section = entry->section; page->metric_id = entry->metric_id; page->start_time_s = entry->start_time_s; page->end_time_s = entry->end_time_s, page->update_every_s = entry->update_every_s, page->data = entry->data; page->assumed_size = page_assumed_size(cache, entry->size); netdata_spinlock_init(&page->transition_spinlock); page->link.prev = NULL; page->link.next = NULL; if(cache->config.additional_bytes_per_page) { if(entry->custom_data) memcpy(page->custom_data, entry->custom_data, cache->config.additional_bytes_per_page); else memset(page->custom_data, 0, cache->config.additional_bytes_per_page); } // put it in the index *page_ptr = page; pointer_add(cache, page); pgc_index_write_unlock(cache, partition); if (entry->hot) page_set_hot(cache, page); else page_set_clean(cache, page, false, false); PGC_REFERENCED_PAGES_PLUS1(cache, page); // update statistics __atomic_add_fetch(&cache->stats.added_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.added_size, page->assumed_size, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.size, page->assumed_size, __ATOMIC_RELAXED); if(added) *added = true; } else { if (!page_acquire(cache, page)) page = NULL; else if(added) *added = false; pgc_index_write_unlock(cache, partition); if(unlikely(!page)) { // now that we don't have the lock, // give it some time for the old page to go away struct timespec ns = { .tv_sec = 0, .tv_nsec = 1 }; nanosleep(&ns, NULL); } } } while(!page); #ifdef PGC_WITH_ARAL if(allocation) aral_freez(cache->aral[partition], allocation); #endif __atomic_sub_fetch(&cache->stats.workers_add, 1, __ATOMIC_RELAXED); if(!entry->hot) evict_on_clean_page_added(cache); if((cache->config.options & PGC_OPTIONS_FLUSH_PAGES_INLINE) || flushing_critical(cache)) { flush_pages(cache, cache->config.max_flushes_inline, PGC_SECTION_ALL, false, false); } return page; } static PGC_PAGE *page_find_and_acquire(PGC *cache, Word_t section, Word_t metric_id, time_t start_time_s, PGC_SEARCH method) { __atomic_add_fetch(&cache->stats.workers_search, 1, __ATOMIC_RELAXED); size_t *stats_hit_ptr, *stats_miss_ptr; if(method == PGC_SEARCH_CLOSEST) { __atomic_add_fetch(&cache->stats.searches_closest, 1, __ATOMIC_RELAXED); stats_hit_ptr = &cache->stats.searches_closest_hits; stats_miss_ptr = &cache->stats.searches_closest_misses; } else { __atomic_add_fetch(&cache->stats.searches_exact, 1, __ATOMIC_RELAXED); stats_hit_ptr = &cache->stats.searches_exact_hits; stats_miss_ptr = &cache->stats.searches_exact_misses; } PGC_PAGE *page = NULL; size_t partition = pgc_indexing_partition(cache, metric_id); pgc_index_read_lock(cache, partition); Pvoid_t *metrics_judy_pptr = JudyLGet(cache->index[partition].sections_judy, section, PJE0); if(unlikely(metrics_judy_pptr == PJERR)) fatal("DBENGINE CACHE: corrupted sections judy array"); if(unlikely(!metrics_judy_pptr)) { // section does not exist goto cleanup; } Pvoid_t *pages_judy_pptr = JudyLGet(*metrics_judy_pptr, metric_id, PJE0); if(unlikely(pages_judy_pptr == PJERR)) fatal("DBENGINE CACHE: corrupted pages judy array"); if(unlikely(!pages_judy_pptr)) { // metric does not exist goto cleanup; } switch(method) { default: case PGC_SEARCH_CLOSEST: { Pvoid_t *page_ptr = JudyLGet(*pages_judy_pptr, start_time_s, PJE0); if (unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array"); if (page_ptr) page = *page_ptr; else { Word_t time = start_time_s; // find the previous page page_ptr = JudyLLast(*pages_judy_pptr, &time, PJE0); if(unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array #2"); if(page_ptr) { // found a page starting before our timestamp // check if our timestamp is included page = *page_ptr; if(start_time_s > page->end_time_s) // it is not good for us page = NULL; } if(!page) { // find the next page then... time = start_time_s; page_ptr = JudyLNext(*pages_judy_pptr, &time, PJE0); if(page_ptr) page = *page_ptr; } } } break; case PGC_SEARCH_EXACT: { Pvoid_t *page_ptr = JudyLGet(*pages_judy_pptr, start_time_s, PJE0); if (unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array"); if (page_ptr) page = *page_ptr; } break; case PGC_SEARCH_FIRST: { Word_t time = start_time_s; Pvoid_t *page_ptr = JudyLFirst(*pages_judy_pptr, &time, PJE0); if (unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array"); if (page_ptr) page = *page_ptr; } break; case PGC_SEARCH_NEXT: { Word_t time = start_time_s; Pvoid_t *page_ptr = JudyLNext(*pages_judy_pptr, &time, PJE0); if (unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array"); if (page_ptr) page = *page_ptr; } break; case PGC_SEARCH_LAST: { Word_t time = start_time_s; Pvoid_t *page_ptr = JudyLLast(*pages_judy_pptr, &time, PJE0); if (unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array"); if (page_ptr) page = *page_ptr; } break; case PGC_SEARCH_PREV: { Word_t time = start_time_s; Pvoid_t *page_ptr = JudyLPrev(*pages_judy_pptr, &time, PJE0); if (unlikely(page_ptr == PJERR)) fatal("DBENGINE CACHE: corrupted page in pages judy array"); if (page_ptr) page = *page_ptr; } break; } if(page) { pointer_check(cache, page); if(!page_acquire(cache, page)) { // this page is not good to use page = NULL; } } cleanup: pgc_index_read_unlock(cache, partition); if(page) { __atomic_add_fetch(stats_hit_ptr, 1, __ATOMIC_RELAXED); page_has_been_accessed(cache, page); } else __atomic_add_fetch(stats_miss_ptr, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.workers_search, 1, __ATOMIC_RELAXED); return page; } static void all_hot_pages_to_dirty(PGC *cache, Word_t section) { pgc_ll_lock(cache, &cache->hot); bool first = true; Word_t last_section = (section == PGC_SECTION_ALL) ? 0 : section; Pvoid_t *section_pages_pptr; while ((section_pages_pptr = JudyLFirstThenNext(cache->hot.sections_judy, &last_section, &first))) { if(section != PGC_SECTION_ALL && last_section != section) break; struct section_pages *sp = *section_pages_pptr; PGC_PAGE *page = sp->base; while(page) { PGC_PAGE *next = page->link.next; if(page_acquire(cache, page)) { page_set_dirty(cache, page, true); page_release(cache, page, false); // page ptr may be invalid now } page = next; } } pgc_ll_unlock(cache, &cache->hot); } // returns true when there is more work to do static bool flush_pages(PGC *cache, size_t max_flushes, Word_t section, bool wait, bool all_of_them) { internal_fatal(!cache->dirty.linked_list_in_sections_judy, "wrong dirty pages configuration - dirty pages need to have a judy array, not a linked list"); if(!all_of_them && !wait) { // we have been called from a data collection thread // let's not waste its time... if(!pgc_ll_trylock(cache, &cache->dirty)) { // we would block, so give up... return true; } // we got the lock at this point } else pgc_ll_lock(cache, &cache->dirty); size_t optimal_flush_size = cache->config.max_dirty_pages_per_call; size_t dirty_version_at_entry = cache->dirty.version; if(!all_of_them && (cache->dirty.stats->entries < optimal_flush_size || cache->dirty.last_version_checked == dirty_version_at_entry)) { pgc_ll_unlock(cache, &cache->dirty); return false; } __atomic_add_fetch(&cache->stats.workers_flush, 1, __ATOMIC_RELAXED); bool have_dirty_lock = true; if(all_of_them || !max_flushes) max_flushes = SIZE_MAX; Word_t last_section = (section == PGC_SECTION_ALL) ? 0 : section; size_t flushes_so_far = 0; Pvoid_t *section_pages_pptr; bool stopped_before_finishing = false; size_t spins = 0; bool first = true; while (have_dirty_lock && (section_pages_pptr = JudyLFirstThenNext(cache->dirty.sections_judy, &last_section, &first))) { if(section != PGC_SECTION_ALL && last_section != section) break; struct section_pages *sp = *section_pages_pptr; if(!all_of_them && sp->entries < optimal_flush_size) continue; if(!all_of_them && flushes_so_far > max_flushes) { stopped_before_finishing = true; break; } if(++spins > 1) __atomic_add_fetch(&cache->stats.flush_spins, 1, __ATOMIC_RELAXED); PGC_ENTRY array[optimal_flush_size]; PGC_PAGE *pages[optimal_flush_size]; size_t pages_added = 0, pages_added_size = 0; size_t pages_removed_dirty = 0, pages_removed_dirty_size = 0; size_t pages_cancelled = 0, pages_cancelled_size = 0; size_t pages_made_clean = 0, pages_made_clean_size = 0; PGC_PAGE *page = sp->base; while (page && pages_added < optimal_flush_size) { PGC_PAGE *next = page->link.next; internal_fatal(page_get_status_flags(page) != PGC_PAGE_DIRTY, "DBENGINE CACHE: page should be in the dirty list before saved"); if (page_acquire(cache, page)) { internal_fatal(page_get_status_flags(page) != PGC_PAGE_DIRTY, "DBENGINE CACHE: page should be in the dirty list before saved"); internal_fatal(page->section != last_section, "DBENGINE CACHE: dirty page is not in the right section (tier)"); if(!page_transition_trylock(cache, page)) { page_release(cache, page, false); // page ptr may be invalid now } else { pages[pages_added] = page; array[pages_added] = (PGC_ENTRY) { .section = page->section, .metric_id = page->metric_id, .start_time_s = page->start_time_s, .end_time_s = __atomic_load_n(&page->end_time_s, __ATOMIC_RELAXED), .update_every_s = page->update_every_s, .size = page_size_from_assumed_size(cache, page->assumed_size), .data = page->data, .custom_data = (cache->config.additional_bytes_per_page) ? page->custom_data : NULL, .hot = false, }; pages_added_size += page->assumed_size; pages_added++; } } page = next; } // do we have enough to save? if(all_of_them || pages_added == optimal_flush_size) { // we should do it for (size_t i = 0; i < pages_added; i++) { PGC_PAGE *tpg = pages[i]; internal_fatal(page_get_status_flags(tpg) != PGC_PAGE_DIRTY, "DBENGINE CACHE: page should be in the dirty list before saved"); __atomic_add_fetch(&cache->stats.flushing_entries, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.flushing_size, tpg->assumed_size, __ATOMIC_RELAXED); // remove it from the dirty list pgc_ll_del(cache, &cache->dirty, tpg, true); pages_removed_dirty_size += tpg->assumed_size; pages_removed_dirty++; } // next time, repeat the same section (tier) first = true; } else { // we can't do it for (size_t i = 0; i < pages_added; i++) { PGC_PAGE *tpg = pages[i]; internal_fatal(page_get_status_flags(tpg) != PGC_PAGE_DIRTY, "DBENGINE CACHE: page should be in the dirty list before saved"); pages_cancelled_size += tpg->assumed_size; pages_cancelled++; page_transition_unlock(cache, tpg); page_release(cache, tpg, false); // page ptr may be invalid now } __atomic_add_fetch(&cache->stats.flushes_cancelled, pages_cancelled, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.flushes_cancelled_size, pages_cancelled_size, __ATOMIC_RELAXED); internal_fatal(pages_added != pages_cancelled || pages_added_size != pages_cancelled_size, "DBENGINE CACHE: flushing cancel pages mismatch"); // next time, continue to the next section (tier) first = false; continue; } if(cache->config.pgc_save_init_cb) cache->config.pgc_save_init_cb(cache, last_section); pgc_ll_unlock(cache, &cache->dirty); have_dirty_lock = false; // call the callback to save them // it may take some time, so let's release the lock cache->config.pgc_save_dirty_cb(cache, array, pages, pages_added); flushes_so_far++; __atomic_add_fetch(&cache->stats.flushes_completed, pages_added, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.flushes_completed_size, pages_added_size, __ATOMIC_RELAXED); size_t pages_to_evict = 0; (void)pages_to_evict; for (size_t i = 0; i < pages_added; i++) { PGC_PAGE *tpg = pages[i]; internal_fatal(page_get_status_flags(tpg) != 0, "DBENGINE CACHE: page should not be in any list while it is being saved"); __atomic_sub_fetch(&cache->stats.flushing_entries, 1, __ATOMIC_RELAXED); __atomic_sub_fetch(&cache->stats.flushing_size, tpg->assumed_size, __ATOMIC_RELAXED); pages_made_clean_size += tpg->assumed_size; pages_made_clean++; if(!tpg->accesses) pages_to_evict++; page_set_clean(cache, tpg, true, false); page_transition_unlock(cache, tpg); page_release(cache, tpg, false); // tpg ptr may be invalid now } internal_fatal(pages_added != pages_made_clean || pages_added != pages_removed_dirty || pages_added_size != pages_made_clean_size || pages_added_size != pages_removed_dirty_size , "DBENGINE CACHE: flushing pages mismatch"); if(!all_of_them && !wait) { if(pgc_ll_trylock(cache, &cache->dirty)) have_dirty_lock = true; else { stopped_before_finishing = true; have_dirty_lock = false; } } else { pgc_ll_lock(cache, &cache->dirty); have_dirty_lock = true; } } if(have_dirty_lock) { if(!stopped_before_finishing && dirty_version_at_entry > cache->dirty.last_version_checked) cache->dirty.last_version_checked = dirty_version_at_entry; pgc_ll_unlock(cache, &cache->dirty); } __atomic_sub_fetch(&cache->stats.workers_flush, 1, __ATOMIC_RELAXED); return stopped_before_finishing; } void free_all_unreferenced_clean_pages(PGC *cache) { evict_pages(cache, 0, 0, true, true); } // ---------------------------------------------------------------------------- // public API PGC *pgc_create(const char *name, size_t clean_size_bytes, free_clean_page_callback pgc_free_cb, size_t max_dirty_pages_per_flush, save_dirty_init_callback pgc_save_init_cb, save_dirty_page_callback pgc_save_dirty_cb, size_t max_pages_per_inline_eviction, size_t max_inline_evictors, size_t max_skip_pages_per_inline_eviction, size_t max_flushes_inline, PGC_OPTIONS options, size_t partitions, size_t additional_bytes_per_page) { if(max_pages_per_inline_eviction < 2) max_pages_per_inline_eviction = 2; if(max_dirty_pages_per_flush < 1) max_dirty_pages_per_flush = 1; if(max_flushes_inline * max_dirty_pages_per_flush < 2) max_flushes_inline = 2; PGC *cache = callocz(1, sizeof(PGC)); strncpyz(cache->config.name, name, PGC_NAME_MAX); cache->config.options = options; cache->config.clean_size = (clean_size_bytes < 1 * 1024 * 1024) ? 1 * 1024 * 1024 : clean_size_bytes; cache->config.pgc_free_clean_cb = pgc_free_cb; cache->config.max_dirty_pages_per_call = max_dirty_pages_per_flush; cache->config.pgc_save_init_cb = pgc_save_init_cb; cache->config.pgc_save_dirty_cb = pgc_save_dirty_cb; cache->config.max_pages_per_inline_eviction = (max_pages_per_inline_eviction < 2) ? 2 : max_pages_per_inline_eviction; cache->config.max_skip_pages_per_inline_eviction = (max_skip_pages_per_inline_eviction < 2) ? 2 : max_skip_pages_per_inline_eviction; cache->config.max_flushes_inline = (max_flushes_inline < 1) ? 1 : max_flushes_inline; cache->config.partitions = partitions < 1 ? (size_t)get_netdata_cpus() : partitions; cache->config.additional_bytes_per_page = additional_bytes_per_page; cache->config.max_workers_evict_inline = max_inline_evictors; cache->config.severe_pressure_per1000 = 1010; cache->config.aggressive_evict_per1000 = 990; cache->config.healthy_size_per1000 = 980; cache->config.evict_low_threshold_per1000 = 970; cache->index = callocz(cache->config.partitions, sizeof(struct pgc_index)); for(size_t part = 0; part < cache->config.partitions ; part++) netdata_rwlock_init(&cache->index[part].rwlock); netdata_spinlock_init(&cache->hot.spinlock); netdata_spinlock_init(&cache->dirty.spinlock); netdata_spinlock_init(&cache->clean.spinlock); cache->hot.flags = PGC_PAGE_HOT; cache->hot.linked_list_in_sections_judy = true; cache->hot.stats = &cache->stats.queues.hot; cache->dirty.flags = PGC_PAGE_DIRTY; cache->dirty.linked_list_in_sections_judy = true; cache->dirty.stats = &cache->stats.queues.dirty; cache->clean.flags = PGC_PAGE_CLEAN; cache->clean.linked_list_in_sections_judy = false; cache->clean.stats = &cache->stats.queues.clean; pgc_section_pages_static_aral_init(); #ifdef PGC_WITH_ARAL cache->aral = callocz(cache->config.partitions, sizeof(ARAL *)); for(size_t part = 0; part < cache->config.partitions ; part++) { char buf[100 +1]; snprintfz(buf, 100, "%s[%zu]", name, part); cache->aral[part] = aral_create( buf, sizeof(PGC_PAGE) + cache->config.additional_bytes_per_page, 0, 16384, aral_statistics(pgc_section_pages_aral), NULL, NULL, false, false); } #endif pointer_index_init(cache); return cache; } struct aral_statistics *pgc_aral_statistics(void) { return aral_statistics(pgc_section_pages_aral); } size_t pgc_aral_structures(void) { return aral_structures(pgc_section_pages_aral); } size_t pgc_aral_overhead(void) { return aral_overhead(pgc_section_pages_aral); } void pgc_flush_all_hot_and_dirty_pages(PGC *cache, Word_t section) { all_hot_pages_to_dirty(cache, section); // save all dirty pages to make them clean flush_pages(cache, 0, section, true, true); } void pgc_destroy(PGC *cache) { // convert all hot pages to dirty all_hot_pages_to_dirty(cache, PGC_SECTION_ALL); // save all dirty pages to make them clean flush_pages(cache, 0, PGC_SECTION_ALL, true, true); // free all unreferenced clean pages free_all_unreferenced_clean_pages(cache); if(PGC_REFERENCED_PAGES(cache)) error("DBENGINE CACHE: there are %zu referenced cache pages - leaving the cache allocated", PGC_REFERENCED_PAGES(cache)); else { pointer_destroy_index(cache); for(size_t part = 0; part < cache->config.partitions ; part++) netdata_rwlock_destroy(&cache->index[part].rwlock); #ifdef PGC_WITH_ARAL for(size_t part = 0; part < cache->config.partitions ; part++) aral_destroy(cache->aral[part]); freez(cache->aral); #endif freez(cache); } } PGC_PAGE *pgc_page_add_and_acquire(PGC *cache, PGC_ENTRY entry, bool *added) { return page_add(cache, &entry, added); } PGC_PAGE *pgc_page_dup(PGC *cache, PGC_PAGE *page) { if(!page_acquire(cache, page)) fatal("DBENGINE CACHE: tried to dup a page that is not acquired!"); return page; } void pgc_page_release(PGC *cache, PGC_PAGE *page) { page_release(cache, page, is_page_clean(page)); } void pgc_page_hot_to_dirty_and_release(PGC *cache, PGC_PAGE *page) { __atomic_add_fetch(&cache->stats.workers_hot2dirty, 1, __ATOMIC_RELAXED); //#ifdef NETDATA_INTERNAL_CHECKS // page_transition_lock(cache, page); // internal_fatal(!is_page_hot(page), "DBENGINE CACHE: called %s() but page is not hot", __FUNCTION__ ); // page_transition_unlock(cache, page); //#endif // make page dirty page_set_dirty(cache, page, false); // release the page page_release(cache, page, true); // page ptr may be invalid now __atomic_sub_fetch(&cache->stats.workers_hot2dirty, 1, __ATOMIC_RELAXED); // flush, if we have to if((cache->config.options & PGC_OPTIONS_FLUSH_PAGES_INLINE) || flushing_critical(cache)) { flush_pages(cache, cache->config.max_flushes_inline, PGC_SECTION_ALL, false, false); } } bool pgc_page_to_clean_evict_or_release(PGC *cache, PGC_PAGE *page) { bool ret; __atomic_add_fetch(&cache->stats.workers_hot2dirty, 1, __ATOMIC_RELAXED); // prevent accesses from increasing the accesses counter page_flag_set(page, PGC_PAGE_HAS_NO_DATA_IGNORE_ACCESSES); // zero the accesses counter __atomic_store_n(&page->accesses, 0, __ATOMIC_RELEASE); // if there are no other references to it, evict it immediately if(make_acquired_page_clean_and_evict_or_page_release(cache, page)) { __atomic_add_fetch(&cache->stats.hot_empty_pages_evicted_immediately, 1, __ATOMIC_RELAXED); ret = true; } else { __atomic_add_fetch(&cache->stats.hot_empty_pages_evicted_later, 1, __ATOMIC_RELAXED); ret = false; } __atomic_sub_fetch(&cache->stats.workers_hot2dirty, 1, __ATOMIC_RELAXED); return ret; } Word_t pgc_page_section(PGC_PAGE *page) { return page->section; } Word_t pgc_page_metric(PGC_PAGE *page) { return page->metric_id; } time_t pgc_page_start_time_s(PGC_PAGE *page) { return page->start_time_s; } time_t pgc_page_end_time_s(PGC_PAGE *page) { return page->end_time_s; } time_t pgc_page_update_every_s(PGC_PAGE *page) { return page->update_every_s; } time_t pgc_page_fix_update_every(PGC_PAGE *page, time_t update_every_s) { if(page->update_every_s == 0) page->update_every_s = update_every_s; return page->update_every_s; } time_t pgc_page_fix_end_time_s(PGC_PAGE *page, time_t end_time_s) { page->end_time_s = end_time_s; return page->end_time_s; } void *pgc_page_data(PGC_PAGE *page) { return page->data; } void *pgc_page_custom_data(PGC *cache, PGC_PAGE *page) { if(cache->config.additional_bytes_per_page) return page->custom_data; return NULL; } size_t pgc_page_data_size(PGC *cache, PGC_PAGE *page) { return page_size_from_assumed_size(cache, page->assumed_size); } bool pgc_is_page_hot(PGC_PAGE *page) { return is_page_hot(page); } bool pgc_is_page_dirty(PGC_PAGE *page) { return is_page_dirty(page); } bool pgc_is_page_clean(PGC_PAGE *page) { return is_page_clean(page); } void pgc_reset_hot_max(PGC *cache) { size_t entries = __atomic_load_n(&cache->hot.stats->entries, __ATOMIC_RELAXED); size_t size = __atomic_load_n(&cache->hot.stats->size, __ATOMIC_RELAXED); __atomic_store_n(&cache->hot.stats->max_entries, entries, __ATOMIC_RELAXED); __atomic_store_n(&cache->hot.stats->max_size, size, __ATOMIC_RELAXED); size_t size_to_evict = 0; cache_usage_per1000(cache, &size_to_evict); evict_pages(cache, 0, 0, true, false); } void pgc_set_dynamic_target_cache_size_callback(PGC *cache, dynamic_target_cache_size_callback callback) { cache->config.dynamic_target_size_cb = callback; size_t size_to_evict = 0; cache_usage_per1000(cache, &size_to_evict); evict_pages(cache, 0, 0, true, false); } size_t pgc_get_current_cache_size(PGC *cache) { cache_usage_per1000(cache, NULL); return __atomic_load_n(&cache->stats.current_cache_size, __ATOMIC_RELAXED); } size_t pgc_get_wanted_cache_size(PGC *cache) { cache_usage_per1000(cache, NULL); return __atomic_load_n(&cache->stats.wanted_cache_size, __ATOMIC_RELAXED); } bool pgc_evict_pages(PGC *cache, size_t max_skip, size_t max_evict) { bool under_pressure = cache_needs_space_aggressively(cache); return evict_pages(cache, under_pressure ? 0 : max_skip, under_pressure ? 0 : max_evict, true, false); } bool pgc_flush_pages(PGC *cache, size_t max_flushes) { bool under_pressure = flushing_critical(cache); return flush_pages(cache, under_pressure ? 0 : max_flushes, PGC_SECTION_ALL, true, false); } void pgc_page_hot_set_end_time_s(PGC *cache __maybe_unused, PGC_PAGE *page, time_t end_time_s) { internal_fatal(!is_page_hot(page), "DBENGINE CACHE: end_time_s update on non-hot page"); internal_fatal(end_time_s < __atomic_load_n(&page->end_time_s, __ATOMIC_RELAXED), "DBENGINE CACHE: end_time_s is not bigger than existing"); __atomic_store_n(&page->end_time_s, end_time_s, __ATOMIC_RELAXED); #ifdef PGC_COUNT_POINTS_COLLECTED __atomic_add_fetch(&cache->stats.points_collected, 1, __ATOMIC_RELAXED); #endif } PGC_PAGE *pgc_page_get_and_acquire(PGC *cache, Word_t section, Word_t metric_id, time_t start_time_s, PGC_SEARCH method) { return page_find_and_acquire(cache, section, metric_id, start_time_s, method); } struct pgc_statistics pgc_get_statistics(PGC *cache) { // FIXME - get the statistics atomically return cache->stats; } size_t pgc_hot_and_dirty_entries(PGC *cache) { size_t entries = 0; entries += __atomic_load_n(&cache->hot.stats->entries, __ATOMIC_RELAXED); entries += __atomic_load_n(&cache->dirty.stats->entries, __ATOMIC_RELAXED); entries += __atomic_load_n(&cache->stats.flushing_entries, __ATOMIC_RELAXED); entries += __atomic_load_n(&cache->stats.hot2dirty_entries, __ATOMIC_RELAXED); return entries; } void pgc_open_cache_to_journal_v2(PGC *cache, Word_t section, unsigned datafile_fileno, uint8_t type, migrate_to_v2_callback cb, void *data) { __atomic_add_fetch(&rrdeng_cache_efficiency_stats.journal_v2_indexing_started, 1, __ATOMIC_RELAXED); __atomic_add_fetch(&cache->stats.workers_jv2_flush, 1, __ATOMIC_RELAXED); pgc_ll_lock(cache, &cache->hot); Pvoid_t JudyL_metrics = NULL; Pvoid_t JudyL_extents_pos = NULL; size_t count_of_unique_extents = 0; size_t count_of_unique_metrics = 0; size_t count_of_unique_pages = 0; size_t master_extent_index_id = 0; Pvoid_t *section_pages_pptr = JudyLGet(cache->hot.sections_judy, section, PJE0); if(!section_pages_pptr) { pgc_ll_unlock(cache, &cache->hot); return; } struct section_pages *sp = *section_pages_pptr; if(!netdata_spinlock_trylock(&sp->migration_to_v2_spinlock)) { internal_fatal(true, "DBENGINE: migration to journal v2 is already running for this section"); pgc_ll_unlock(cache, &cache->hot); return; } ARAL *ar_mi = aral_by_size_acquire(sizeof(struct jv2_metrics_info)); ARAL *ar_pi = aral_by_size_acquire(sizeof(struct jv2_page_info)); ARAL *ar_ei = aral_by_size_acquire(sizeof(struct jv2_extents_info)); for(PGC_PAGE *page = sp->base; page ; page = page->link.next) { struct extent_io_data *xio = (struct extent_io_data *)page->custom_data; if(xio->fileno != datafile_fileno) continue; if(page_flag_check(page, PGC_PAGE_IS_BEING_MIGRATED_TO_V2)) { internal_fatal(true, "Migration to journal v2: page has already been migrated to v2"); continue; } if(!page_transition_trylock(cache, page)) { internal_fatal(true, "Migration to journal v2: cannot get page transition lock"); continue; } if(!page_acquire(cache, page)) { internal_fatal(true, "Migration to journal v2: cannot acquire page for migration to v2"); continue; } page_flag_set(page, PGC_PAGE_IS_BEING_MIGRATED_TO_V2); pgc_ll_unlock(cache, &cache->hot); // update the extents JudyL size_t current_extent_index_id; Pvoid_t *PValue = JudyLIns(&JudyL_extents_pos, xio->pos, PJE0); if(!PValue || *PValue == PJERR) fatal("Corrupted JudyL extents pos"); struct jv2_extents_info *ei; if(!*PValue) { ei = aral_mallocz(ar_ei); // callocz(1, sizeof(struct jv2_extents_info)); ei->pos = xio->pos; ei->bytes = xio->bytes; ei->number_of_pages = 1; ei->index = master_extent_index_id++; *PValue = ei; count_of_unique_extents++; } else { ei = *PValue; ei->number_of_pages++; } current_extent_index_id = ei->index; // update the metrics JudyL PValue = JudyLIns(&JudyL_metrics, page->metric_id, PJE0); if(!PValue || *PValue == PJERR) fatal("Corrupted JudyL metrics"); struct jv2_metrics_info *mi; if(!*PValue) { mi = aral_mallocz(ar_mi); // callocz(1, sizeof(struct jv2_metrics_info)); mi->uuid = mrg_metric_uuid(main_mrg, (METRIC *)page->metric_id); mi->first_time_s = page->start_time_s; mi->last_time_s = page->end_time_s; mi->number_of_pages = 1; mi->page_list_header = 0; mi->JudyL_pages_by_start_time = NULL; *PValue = mi; count_of_unique_metrics++; } else { mi = *PValue; mi->number_of_pages++; if(page->start_time_s < mi->first_time_s) mi->first_time_s = page->start_time_s; if(page->end_time_s > mi->last_time_s) mi->last_time_s = page->end_time_s; } PValue = JudyLIns(&mi->JudyL_pages_by_start_time, page->start_time_s, PJE0); if(!PValue || *PValue == PJERR) fatal("Corrupted JudyL metric pages"); if(!*PValue) { struct jv2_page_info *pi = aral_mallocz(ar_pi); // callocz(1, (sizeof(struct jv2_page_info))); pi->start_time_s = page->start_time_s; pi->end_time_s = page->end_time_s; pi->update_every_s = page->update_every_s; pi->page_length = page_size_from_assumed_size(cache, page->assumed_size); pi->page = page; pi->extent_index = current_extent_index_id; pi->custom_data = (cache->config.additional_bytes_per_page) ? page->custom_data : NULL; *PValue = pi; count_of_unique_pages++; } else { // impossible situation internal_fatal(true, "Page is already in JudyL metric pages"); page_flag_clear(page, PGC_PAGE_IS_BEING_MIGRATED_TO_V2); page_transition_unlock(cache, page); page_release(cache, page, false); } pgc_ll_lock(cache, &cache->hot); } netdata_spinlock_unlock(&sp->migration_to_v2_spinlock); pgc_ll_unlock(cache, &cache->hot); // callback cb(section, datafile_fileno, type, JudyL_metrics, JudyL_extents_pos, count_of_unique_extents, count_of_unique_metrics, count_of_unique_pages, data); { Pvoid_t *PValue1; bool metric_id_first = true; Word_t metric_id = 0; while ((PValue1 = JudyLFirstThenNext(JudyL_metrics, &metric_id, &metric_id_first))) { struct jv2_metrics_info *mi = *PValue1; Pvoid_t *PValue2; bool start_time_first = true; Word_t start_time = 0; while ((PValue2 = JudyLFirstThenNext(mi->JudyL_pages_by_start_time, &start_time, &start_time_first))) { struct jv2_page_info *pi = *PValue2; page_transition_unlock(cache, pi->page); pgc_page_hot_to_dirty_and_release(cache, pi->page); // make_acquired_page_clean_and_evict_or_page_release(cache, pi->page); aral_freez(ar_pi, pi); } JudyLFreeArray(&mi->JudyL_pages_by_start_time, PJE0); aral_freez(ar_mi, mi); } JudyLFreeArray(&JudyL_metrics, PJE0); } { Pvoid_t *PValue; bool extent_pos_first = true; Word_t extent_pos = 0; while ((PValue = JudyLFirstThenNext(JudyL_extents_pos, &extent_pos, &extent_pos_first))) { struct jv2_extents_info *ei = *PValue; aral_freez(ar_ei, ei); } JudyLFreeArray(&JudyL_extents_pos, PJE0); } aral_by_size_release(ar_ei); aral_by_size_release(ar_pi); aral_by_size_release(ar_mi); __atomic_sub_fetch(&cache->stats.workers_jv2_flush, 1, __ATOMIC_RELAXED); } static bool match_page_data(PGC_PAGE *page, void *data) { return (page->data == data); } void pgc_open_evict_clean_pages_of_datafile(PGC *cache, struct rrdengine_datafile *datafile) { evict_pages_with_filter(cache, 0, 0, true, true, match_page_data, datafile); } size_t pgc_count_clean_pages_having_data_ptr(PGC *cache, Word_t section, void *ptr) { size_t found = 0; pgc_ll_lock(cache, &cache->clean); for(PGC_PAGE *page = cache->clean.base; page ;page = page->link.next) found += (page->data == ptr && page->section == section) ? 1 : 0; pgc_ll_unlock(cache, &cache->clean); return found; } size_t pgc_count_hot_pages_having_data_ptr(PGC *cache, Word_t section, void *ptr) { size_t found = 0; pgc_ll_lock(cache, &cache->hot); Pvoid_t *section_pages_pptr = JudyLGet(cache->hot.sections_judy, section, PJE0); if(section_pages_pptr) { struct section_pages *sp = *section_pages_pptr; for(PGC_PAGE *page = sp->base; page ;page = page->link.next) found += (page->data == ptr) ? 1 : 0; } pgc_ll_unlock(cache, &cache->hot); return found; } // ---------------------------------------------------------------------------- // unittest static void unittest_free_clean_page_callback(PGC *cache __maybe_unused, PGC_ENTRY entry __maybe_unused) { ; } static void unittest_save_dirty_page_callback(PGC *cache __maybe_unused, PGC_ENTRY *entries_array __maybe_unused, PGC_PAGE **pages_array __maybe_unused, size_t entries __maybe_unused) { ; } #ifdef PGC_STRESS_TEST struct { bool stop; PGC *cache; PGC_PAGE **metrics; size_t clean_metrics; size_t hot_metrics; time_t first_time_t; time_t last_time_t; size_t cache_size; size_t query_threads; size_t collect_threads; size_t partitions; size_t points_per_page; time_t time_per_collection_ut; time_t time_per_query_ut; time_t time_per_flush_ut; PGC_OPTIONS options; char rand_statebufs[1024]; struct random_data *random_data; } pgc_uts = { .stop = false, .metrics = NULL, .clean_metrics = 100000, .hot_metrics = 1000000, .first_time_t = 100000000, .last_time_t = 0, .cache_size = 0, // get the default (8MB) .collect_threads = 16, .query_threads = 16, .partitions = 0, // get the default (system cpus) .options = PGC_OPTIONS_AUTOSCALE,/* PGC_OPTIONS_FLUSH_PAGES_INLINE | PGC_OPTIONS_EVICT_PAGES_INLINE,*/ .points_per_page = 10, .time_per_collection_ut = 1000000, .time_per_query_ut = 250, .time_per_flush_ut = 100, .rand_statebufs = {}, .random_data = NULL, }; void *unittest_stress_test_collector(void *ptr) { size_t id = *((size_t *)ptr); size_t metric_start = pgc_uts.clean_metrics; size_t metric_end = pgc_uts.clean_metrics + pgc_uts.hot_metrics; size_t number_of_metrics = metric_end - metric_start; size_t per_collector_metrics = number_of_metrics / pgc_uts.collect_threads; metric_start = metric_start + per_collector_metrics * id + 1; metric_end = metric_start + per_collector_metrics - 1; time_t start_time_t = pgc_uts.first_time_t + 1; heartbeat_t hb; heartbeat_init(&hb); while(!__atomic_load_n(&pgc_uts.stop, __ATOMIC_RELAXED)) { // info("COLLECTOR %zu: collecting metrics %zu to %zu, from %ld to %lu", id, metric_start, metric_end, start_time_t, start_time_t + pgc_uts.points_per_page); netdata_thread_disable_cancelability(); for (size_t i = metric_start; i < metric_end; i++) { bool added; pgc_uts.metrics[i] = pgc_page_add_and_acquire(pgc_uts.cache, (PGC_ENTRY) { .section = 1, .metric_id = i, .start_time_t = start_time_t, .end_time_t = start_time_t, .update_every = 1, .size = 4096, .data = NULL, .hot = true, }, &added); if(!pgc_is_page_hot(pgc_uts.metrics[i]) || !added) { pgc_page_release(pgc_uts.cache, pgc_uts.metrics[i]); pgc_uts.metrics[i] = NULL; } } time_t end_time_t = start_time_t + (time_t)pgc_uts.points_per_page; while(++start_time_t <= end_time_t && !__atomic_load_n(&pgc_uts.stop, __ATOMIC_RELAXED)) { heartbeat_next(&hb, pgc_uts.time_per_collection_ut); for (size_t i = metric_start; i < metric_end; i++) { if(pgc_uts.metrics[i]) pgc_page_hot_set_end_time_t(pgc_uts.cache, pgc_uts.metrics[i], start_time_t); } __atomic_store_n(&pgc_uts.last_time_t, start_time_t, __ATOMIC_RELAXED); } for (size_t i = metric_start; i < metric_end; i++) { if (pgc_uts.metrics[i]) { if(i % 10 == 0) pgc_page_to_clean_evict_or_release(pgc_uts.cache, pgc_uts.metrics[i]); else pgc_page_hot_to_dirty_and_release(pgc_uts.cache, pgc_uts.metrics[i]); } } netdata_thread_enable_cancelability(); } return ptr; } void *unittest_stress_test_queries(void *ptr) { size_t id = *((size_t *)ptr); struct random_data *random_data = &pgc_uts.random_data[id]; size_t start = 0; size_t end = pgc_uts.clean_metrics + pgc_uts.hot_metrics; while(!__atomic_load_n(&pgc_uts.stop, __ATOMIC_RELAXED)) { netdata_thread_disable_cancelability(); int32_t random_number; random_r(random_data, &random_number); size_t metric_id = random_number % (end - start); time_t start_time_t = pgc_uts.first_time_t; time_t end_time_t = __atomic_load_n(&pgc_uts.last_time_t, __ATOMIC_RELAXED); if(end_time_t <= start_time_t) end_time_t = start_time_t + 1; size_t pages = (end_time_t - start_time_t) / pgc_uts.points_per_page + 1; PGC_PAGE *array[pages]; for(size_t i = 0; i < pages ;i++) array[i] = NULL; // find the pages the cache has for(size_t i = 0; i < pages ;i++) { time_t page_start_time = start_time_t + (time_t)(i * pgc_uts.points_per_page); array[i] = pgc_page_get_and_acquire(pgc_uts.cache, 1, metric_id, page_start_time, (i < pages - 1)?PGC_SEARCH_EXACT:PGC_SEARCH_CLOSEST); } // load the rest of the pages for(size_t i = 0; i < pages ;i++) { if(array[i]) continue; time_t page_start_time = start_time_t + (time_t)(i * pgc_uts.points_per_page); array[i] = pgc_page_add_and_acquire(pgc_uts.cache, (PGC_ENTRY) { .section = 1, .metric_id = metric_id, .start_time_t = page_start_time, .end_time_t = page_start_time + (time_t)pgc_uts.points_per_page, .update_every = 1, .size = 4096, .data = NULL, .hot = false, }, NULL); } // do the query // ... struct timespec work_duration = {.tv_sec = 0, .tv_nsec = pgc_uts.time_per_query_ut * NSEC_PER_USEC }; nanosleep(&work_duration, NULL); // release the pages for(size_t i = 0; i < pages ;i++) { if(!array[i]) continue; pgc_page_release(pgc_uts.cache, array[i]); array[i] = NULL; } netdata_thread_enable_cancelability(); } return ptr; } void *unittest_stress_test_service(void *ptr) { heartbeat_t hb; heartbeat_init(&hb); while(!__atomic_load_n(&pgc_uts.stop, __ATOMIC_RELAXED)) { heartbeat_next(&hb, 1 * USEC_PER_SEC); pgc_flush_pages(pgc_uts.cache, 1000); pgc_evict_pages(pgc_uts.cache, 0, 0); } return ptr; } static void unittest_stress_test_save_dirty_page_callback(PGC *cache __maybe_unused, PGC_ENTRY *entries_array __maybe_unused, PGC_PAGE **pages_array __maybe_unused, size_t entries __maybe_unused) { // info("SAVE %zu pages", entries); if(!pgc_uts.stop) { usec_t t = pgc_uts.time_per_flush_ut; if(t > 0) { struct timespec work_duration = { .tv_sec = t / USEC_PER_SEC, .tv_nsec = (long) ((t % USEC_PER_SEC) * NSEC_PER_USEC) }; nanosleep(&work_duration, NULL); } } } void unittest_stress_test(void) { pgc_uts.cache = pgc_create(pgc_uts.cache_size * 1024 * 1024, unittest_free_clean_page_callback, 64, unittest_stress_test_save_dirty_page_callback, 1000, 10000, 1, pgc_uts.options, pgc_uts.partitions, 0); pgc_uts.metrics = callocz(pgc_uts.clean_metrics + pgc_uts.hot_metrics, sizeof(PGC_PAGE *)); pthread_t service_thread; netdata_thread_create(&service_thread, "SERVICE", NETDATA_THREAD_OPTION_JOINABLE | NETDATA_THREAD_OPTION_DONT_LOG, unittest_stress_test_service, NULL); pthread_t collect_threads[pgc_uts.collect_threads]; size_t collect_thread_ids[pgc_uts.collect_threads]; for(size_t i = 0; i < pgc_uts.collect_threads ;i++) { collect_thread_ids[i] = i; char buffer[100 + 1]; snprintfz(buffer, 100, "COLLECT_%zu", i); netdata_thread_create(&collect_threads[i], buffer, NETDATA_THREAD_OPTION_JOINABLE | NETDATA_THREAD_OPTION_DONT_LOG, unittest_stress_test_collector, &collect_thread_ids[i]); } pthread_t queries_threads[pgc_uts.query_threads]; size_t query_thread_ids[pgc_uts.query_threads]; pgc_uts.random_data = callocz(pgc_uts.query_threads, sizeof(struct random_data)); for(size_t i = 0; i < pgc_uts.query_threads ;i++) { query_thread_ids[i] = i; char buffer[100 + 1]; snprintfz(buffer, 100, "QUERY_%zu", i); initstate_r(1, pgc_uts.rand_statebufs, 1024, &pgc_uts.random_data[i]); netdata_thread_create(&queries_threads[i], buffer, NETDATA_THREAD_OPTION_JOINABLE | NETDATA_THREAD_OPTION_DONT_LOG, unittest_stress_test_queries, &query_thread_ids[i]); } heartbeat_t hb; heartbeat_init(&hb); struct { size_t entries; size_t added; size_t deleted; size_t referenced; size_t hot_entries; size_t hot_added; size_t hot_deleted; size_t dirty_entries; size_t dirty_added; size_t dirty_deleted; size_t clean_entries; size_t clean_added; size_t clean_deleted; size_t searches_exact; size_t searches_exact_hits; size_t searches_closest; size_t searches_closest_hits; size_t collections; size_t events_cache_under_severe_pressure; size_t events_cache_needs_space_90; size_t events_flush_critical; } stats = {}, old_stats = {}; for(int i = 0; i < 86400 ;i++) { heartbeat_next(&hb, 1 * USEC_PER_SEC); old_stats = stats; stats.entries = __atomic_load_n(&pgc_uts.cache->stats.entries, __ATOMIC_RELAXED); stats.added = __atomic_load_n(&pgc_uts.cache->stats.added_entries, __ATOMIC_RELAXED); stats.deleted = __atomic_load_n(&pgc_uts.cache->stats.removed_entries, __ATOMIC_RELAXED); stats.referenced = __atomic_load_n(&pgc_uts.cache->stats.referenced_entries, __ATOMIC_RELAXED); stats.hot_entries = __atomic_load_n(&pgc_uts.cache->hot.stats->entries, __ATOMIC_RELAXED); stats.hot_added = __atomic_load_n(&pgc_uts.cache->hot.stats->added_entries, __ATOMIC_RELAXED); stats.hot_deleted = __atomic_load_n(&pgc_uts.cache->hot.stats->removed_entries, __ATOMIC_RELAXED); stats.dirty_entries = __atomic_load_n(&pgc_uts.cache->dirty.stats->entries, __ATOMIC_RELAXED); stats.dirty_added = __atomic_load_n(&pgc_uts.cache->dirty.stats->added_entries, __ATOMIC_RELAXED); stats.dirty_deleted = __atomic_load_n(&pgc_uts.cache->dirty.stats->removed_entries, __ATOMIC_RELAXED); stats.clean_entries = __atomic_load_n(&pgc_uts.cache->clean.stats->entries, __ATOMIC_RELAXED); stats.clean_added = __atomic_load_n(&pgc_uts.cache->clean.stats->added_entries, __ATOMIC_RELAXED); stats.clean_deleted = __atomic_load_n(&pgc_uts.cache->clean.stats->removed_entries, __ATOMIC_RELAXED); stats.searches_exact = __atomic_load_n(&pgc_uts.cache->stats.searches_exact, __ATOMIC_RELAXED); stats.searches_exact_hits = __atomic_load_n(&pgc_uts.cache->stats.searches_exact_hits, __ATOMIC_RELAXED); stats.searches_closest = __atomic_load_n(&pgc_uts.cache->stats.searches_closest, __ATOMIC_RELAXED); stats.searches_closest_hits = __atomic_load_n(&pgc_uts.cache->stats.searches_closest_hits, __ATOMIC_RELAXED); stats.events_cache_under_severe_pressure = __atomic_load_n(&pgc_uts.cache->stats.events_cache_under_severe_pressure, __ATOMIC_RELAXED); stats.events_cache_needs_space_90 = __atomic_load_n(&pgc_uts.cache->stats.events_cache_needs_space_aggressively, __ATOMIC_RELAXED); stats.events_flush_critical = __atomic_load_n(&pgc_uts.cache->stats.events_flush_critical, __ATOMIC_RELAXED); size_t searches_exact = stats.searches_exact - old_stats.searches_exact; size_t searches_closest = stats.searches_closest - old_stats.searches_closest; size_t hit_exact = stats.searches_exact_hits - old_stats.searches_exact_hits; size_t hit_closest = stats.searches_closest_hits - old_stats.searches_closest_hits; double hit_exact_pc = (searches_exact > 0) ? (double)hit_exact * 100.0 / (double)searches_exact : 0.0; double hit_closest_pc = (searches_closest > 0) ? (double)hit_closest * 100.0 / (double)searches_closest : 0.0; #ifdef PGC_COUNT_POINTS_COLLECTED stats.collections = __atomic_load_n(&pgc_uts.cache->stats.points_collected, __ATOMIC_RELAXED); #endif char *cache_status = "N"; if(stats.events_cache_under_severe_pressure > old_stats.events_cache_under_severe_pressure) cache_status = "F"; else if(stats.events_cache_needs_space_90 > old_stats.events_cache_needs_space_90) cache_status = "f"; char *flushing_status = "N"; if(stats.events_flush_critical > old_stats.events_flush_critical) flushing_status = "F"; info("PGS %5zuk +%4zuk/-%4zuk " "| RF %5zuk " "| HOT %5zuk +%4zuk -%4zuk " "| DRT %s %5zuk +%4zuk -%4zuk " "| CLN %s %5zuk +%4zuk -%4zuk " "| SRCH %4zuk %4zuk, HIT %4.1f%% %4.1f%% " #ifdef PGC_COUNT_POINTS_COLLECTED "| CLCT %8.4f Mps" #endif , stats.entries / 1000 , (stats.added - old_stats.added) / 1000, (stats.deleted - old_stats.deleted) / 1000 , stats.referenced / 1000 , stats.hot_entries / 1000, (stats.hot_added - old_stats.hot_added) / 1000, (stats.hot_deleted - old_stats.hot_deleted) / 1000 , flushing_status , stats.dirty_entries / 1000 , (stats.dirty_added - old_stats.dirty_added) / 1000, (stats.dirty_deleted - old_stats.dirty_deleted) / 1000 , cache_status , stats.clean_entries / 1000 , (stats.clean_added - old_stats.clean_added) / 1000, (stats.clean_deleted - old_stats.clean_deleted) / 1000 , searches_exact / 1000, searches_closest / 1000 , hit_exact_pc, hit_closest_pc #ifdef PGC_COUNT_POINTS_COLLECTED , (double)(stats.collections - old_stats.collections) / 1000.0 / 1000.0 #endif ); } info("Waiting for threads to stop..."); __atomic_store_n(&pgc_uts.stop, true, __ATOMIC_RELAXED); netdata_thread_join(service_thread, NULL); for(size_t i = 0; i < pgc_uts.collect_threads ;i++) netdata_thread_join(collect_threads[i],NULL); for(size_t i = 0; i < pgc_uts.query_threads ;i++) netdata_thread_join(queries_threads[i],NULL); pgc_destroy(pgc_uts.cache); freez(pgc_uts.metrics); freez(pgc_uts.random_data); } #endif int pgc_unittest(void) { PGC *cache = pgc_create("test", 32 * 1024 * 1024, unittest_free_clean_page_callback, 64, NULL, unittest_save_dirty_page_callback, 10, 10, 1000, 10, PGC_OPTIONS_DEFAULT, 1, 11); // FIXME - unit tests // - add clean page // - add clean page again (should not add it) // - release page (should decrement counters) // - add hot page // - add hot page again (should not add it) // - turn hot page to dirty, with and without a reference counter to it // - dirty pages are saved once there are enough of them // - find page exact // - find page (should return last) // - find page (should return next) // - page cache full (should evict) // - on destroy, turn hot pages to dirty and save them PGC_PAGE *page1 = pgc_page_add_and_acquire(cache, (PGC_ENTRY){ .section = 1, .metric_id = 10, .start_time_s = 100, .end_time_s = 1000, .size = 4096, .data = NULL, .hot = false, .custom_data = (uint8_t *)"0123456789", }, NULL); if(strcmp(pgc_page_custom_data(cache, page1), "0123456789") != 0) fatal("custom data do not work"); memcpy(pgc_page_custom_data(cache, page1), "ABCDEFGHIJ", 11); if(strcmp(pgc_page_custom_data(cache, page1), "ABCDEFGHIJ") != 0) fatal("custom data do not work"); pgc_page_release(cache, page1); PGC_PAGE *page2 = pgc_page_add_and_acquire(cache, (PGC_ENTRY){ .section = 2, .metric_id = 10, .start_time_s = 1001, .end_time_s = 2000, .size = 4096, .data = NULL, .hot = true, }, NULL); pgc_page_hot_set_end_time_s(cache, page2, 2001); pgc_page_hot_to_dirty_and_release(cache, page2); PGC_PAGE *page3 = pgc_page_add_and_acquire(cache, (PGC_ENTRY){ .section = 3, .metric_id = 10, .start_time_s = 1001, .end_time_s = 2000, .size = 4096, .data = NULL, .hot = true, }, NULL); pgc_page_hot_set_end_time_s(cache, page3, 2001); pgc_page_hot_to_dirty_and_release(cache, page3); pgc_destroy(cache); #ifdef PGC_STRESS_TEST unittest_stress_test(); #endif return 0; }