diff options
Diffstat (limited to 'database/engine/pagecache.c')
| -rw-r--r-- | database/engine/pagecache.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/database/engine/pagecache.c b/database/engine/pagecache.c index 1bd4c9436..457bcb218 100644 --- a/database/engine/pagecache.c +++ b/database/engine/pagecache.c @@ -216,6 +216,9 @@ static void pg_cache_release_pages(struct rrdengine_instance *ctx, unsigned numb static void pg_cache_reserve_pages(struct rrdengine_instance *ctx, unsigned number) { struct page_cache *pg_cache = &ctx->pg_cache; + unsigned failures = 0; + const unsigned FAILURES_CEILING = 10; /* truncates exponential backoff to (2^FAILURES_CEILING x slot) */ + unsigned long exp_backoff_slot_usec = USEC_PER_MS * 10; assert(number < ctx->max_cache_pages); @@ -224,11 +227,13 @@ static void pg_cache_reserve_pages(struct rrdengine_instance *ctx, unsigned numb debug(D_RRDENGINE, "==Page cache full. Reserving %u pages.==", number); while (pg_cache->populated_pages + number >= ctx->max_cache_pages + 1) { + if (!pg_cache_try_evict_one_page_unsafe(ctx)) { /* failed to evict */ struct completion compl; struct rrdeng_cmd cmd; + ++failures; uv_rwlock_wrunlock(&pg_cache->pg_cache_rwlock); init_completion(&compl); @@ -240,6 +245,12 @@ static void pg_cache_reserve_pages(struct rrdengine_instance *ctx, unsigned numb wait_for_completion(&compl); destroy_completion(&compl); + if (unlikely(failures > 1)) { + unsigned long slots; + /* exponential backoff */ + slots = random() % (2LU << MIN(failures, FAILURES_CEILING)); + (void)sleep_usec(slots * exp_backoff_slot_usec); + } uv_rwlock_wrlock(&pg_cache->pg_cache_rwlock); } } @@ -1042,9 +1053,8 @@ void free_page_cache(struct rrdengine_instance *ctx) /* Find first page in range */ Index = (Word_t) 0; PValue = JudyLFirst(page_index->JudyL_array, &Index, PJE0); - if (likely(NULL != PValue)) { - descr = *PValue; - } + descr = unlikely(NULL == PValue) ? NULL : *PValue; + while (descr != NULL) { /* Iterate all page descriptors of this metric */ |