Adding upstream version 15.4.upstream/15.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 701 insertions, 0 deletions

diff --git a/src/include/pgstat.h b/src/include/pgstat.h
new file mode 100644
index 0000000..44279ea
--- /dev/null
+++ b/src/include/pgstat.h
@@ -0,0 +1,701 @@
+/* ----------
+ *	pgstat.h
+ *
+ *	Definitions for the PostgreSQL cumulative statistics system.
+ *
+ *	Copyright (c) 2001-2022, PostgreSQL Global Development Group
+ *
+ *	src/include/pgstat.h
+ * ----------
+ */
+#ifndef PGSTAT_H
+#define PGSTAT_H
+
+#include "datatype/timestamp.h"
+#include "portability/instr_time.h"
+#include "postmaster/pgarch.h"	/* for MAX_XFN_CHARS */
+#include "utils/backend_progress.h" /* for backward compatibility */
+#include "utils/backend_status.h"	/* for backward compatibility */
+#include "utils/relcache.h"
+#include "utils/wait_event.h"	/* for backward compatibility */
+
+
+/* ----------
+ * Paths for the statistics files (relative to installation's $PGDATA).
+ * ----------
+ */
+#define PGSTAT_STAT_PERMANENT_DIRECTORY		"pg_stat"
+#define PGSTAT_STAT_PERMANENT_FILENAME		"pg_stat/pgstat.stat"
+#define PGSTAT_STAT_PERMANENT_TMPFILE		"pg_stat/pgstat.tmp"
+
+/* Default directory to store temporary statistics data in */
+#define PG_STAT_TMP_DIR		"pg_stat_tmp"
+
+/* The types of statistics entries */
+typedef enum PgStat_Kind
+{
+	/* use 0 for INVALID, to catch zero-initialized data */
+	PGSTAT_KIND_INVALID = 0,
+
+	/* stats for variable-numbered objects */
+	PGSTAT_KIND_DATABASE,		/* database-wide statistics */
+	PGSTAT_KIND_RELATION,		/* per-table statistics */
+	PGSTAT_KIND_FUNCTION,		/* per-function statistics */
+	PGSTAT_KIND_REPLSLOT,		/* per-slot statistics */
+	PGSTAT_KIND_SUBSCRIPTION,	/* per-subscription statistics */
+
+	/* stats for fixed-numbered objects */
+	PGSTAT_KIND_ARCHIVER,
+	PGSTAT_KIND_BGWRITER,
+	PGSTAT_KIND_CHECKPOINTER,
+	PGSTAT_KIND_SLRU,
+	PGSTAT_KIND_WAL,
+} PgStat_Kind;
+
+#define PGSTAT_KIND_FIRST_VALID PGSTAT_KIND_DATABASE
+#define PGSTAT_KIND_LAST PGSTAT_KIND_WAL
+#define PGSTAT_NUM_KINDS (PGSTAT_KIND_LAST + 1)
+
+/* Values for track_functions GUC variable --- order is significant! */
+typedef enum TrackFunctionsLevel
+{
+	TRACK_FUNC_OFF,
+	TRACK_FUNC_PL,
+	TRACK_FUNC_ALL
+}			TrackFunctionsLevel;
+
+typedef enum PgStat_FetchConsistency
+{
+	PGSTAT_FETCH_CONSISTENCY_NONE,
+	PGSTAT_FETCH_CONSISTENCY_CACHE,
+	PGSTAT_FETCH_CONSISTENCY_SNAPSHOT,
+} PgStat_FetchConsistency;
+
+/* Values to track the cause of session termination */
+typedef enum SessionEndType
+{
+	DISCONNECT_NOT_YET,			/* still active */
+	DISCONNECT_NORMAL,
+	DISCONNECT_CLIENT_EOF,
+	DISCONNECT_FATAL,
+	DISCONNECT_KILLED
+} SessionEndType;
+
+/* ----------
+ * The data type used for counters.
+ * ----------
+ */
+typedef int64 PgStat_Counter;
+
+
+/* ------------------------------------------------------------
+ * Structures kept in backend local memory while accumulating counts
+ * ------------------------------------------------------------
+ */
+
+/* ----------
+ * PgStat_FunctionCounts	The actual per-function counts kept by a backend
+ *
+ * This struct should contain only actual event counters, because we memcmp
+ * it against zeroes to detect whether there are any pending stats.
+ *
+ * Note that the time counters are in instr_time format here.  We convert to
+ * microseconds in PgStat_Counter format when flushing out pending statistics.
+ * ----------
+ */
+typedef struct PgStat_FunctionCounts
+{
+	PgStat_Counter f_numcalls;
+	instr_time	f_total_time;
+	instr_time	f_self_time;
+} PgStat_FunctionCounts;
+
+/* ----------
+ * PgStat_BackendFunctionEntry	Non-flushed function stats.
+ * ----------
+ */
+typedef struct PgStat_BackendFunctionEntry
+{
+	PgStat_FunctionCounts f_counts;
+} PgStat_BackendFunctionEntry;
+
+/*
+ * Working state needed to accumulate per-function-call timing statistics.
+ */
+typedef struct PgStat_FunctionCallUsage
+{
+	/* Link to function's hashtable entry (must still be there at exit!) */
+	/* NULL means we are not tracking the current function call */
+	PgStat_FunctionCounts *fs;
+	/* Total time previously charged to function, as of function start */
+	instr_time	save_f_total_time;
+	/* Backend-wide total time as of function start */
+	instr_time	save_total;
+	/* system clock as of function start */
+	instr_time	f_start;
+} PgStat_FunctionCallUsage;
+
+/* ----------
+ * PgStat_BackendSubEntry	Non-flushed subscription stats.
+ * ----------
+ */
+typedef struct PgStat_BackendSubEntry
+{
+	PgStat_Counter apply_error_count;
+	PgStat_Counter sync_error_count;
+} PgStat_BackendSubEntry;
+
+/* ----------
+ * PgStat_TableCounts			The actual per-table counts kept by a backend
+ *
+ * This struct should contain only actual event counters, because we memcmp
+ * it against zeroes to detect whether there are any stats updates to apply.
+ * It is a component of PgStat_TableStatus (within-backend state).
+ *
+ * Note: for a table, tuples_returned is the number of tuples successfully
+ * fetched by heap_getnext, while tuples_fetched is the number of tuples
+ * successfully fetched by heap_fetch under the control of bitmap indexscans.
+ * For an index, tuples_returned is the number of index entries returned by
+ * the index AM, while tuples_fetched is the number of tuples successfully
+ * fetched by heap_fetch under the control of simple indexscans for this index.
+ *
+ * tuples_inserted/updated/deleted/hot_updated count attempted actions,
+ * regardless of whether the transaction committed.  delta_live_tuples,
+ * delta_dead_tuples, and changed_tuples are set depending on commit or abort.
+ * Note that delta_live_tuples and delta_dead_tuples can be negative!
+ * ----------
+ */
+typedef struct PgStat_TableCounts
+{
+	PgStat_Counter t_numscans;
+
+	PgStat_Counter t_tuples_returned;
+	PgStat_Counter t_tuples_fetched;
+
+	PgStat_Counter t_tuples_inserted;
+	PgStat_Counter t_tuples_updated;
+	PgStat_Counter t_tuples_deleted;
+	PgStat_Counter t_tuples_hot_updated;
+	bool		t_truncdropped;
+
+	PgStat_Counter t_delta_live_tuples;
+	PgStat_Counter t_delta_dead_tuples;
+	PgStat_Counter t_changed_tuples;
+
+	PgStat_Counter t_blocks_fetched;
+	PgStat_Counter t_blocks_hit;
+} PgStat_TableCounts;
+
+/* ----------
+ * PgStat_TableStatus			Per-table status within a backend
+ *
+ * Many of the event counters are nontransactional, ie, we count events
+ * in committed and aborted transactions alike.  For these, we just count
+ * directly in the PgStat_TableStatus.  However, delta_live_tuples,
+ * delta_dead_tuples, and changed_tuples must be derived from event counts
+ * with awareness of whether the transaction or subtransaction committed or
+ * aborted.  Hence, we also keep a stack of per-(sub)transaction status
+ * records for every table modified in the current transaction.  At commit
+ * or abort, we propagate tuples_inserted/updated/deleted up to the
+ * parent subtransaction level, or out to the parent PgStat_TableStatus,
+ * as appropriate.
+ * ----------
+ */
+typedef struct PgStat_TableStatus
+{
+	Oid			t_id;			/* table's OID */
+	bool		t_shared;		/* is it a shared catalog? */
+	struct PgStat_TableXactStatus *trans;	/* lowest subxact's counts */
+	PgStat_TableCounts t_counts;	/* event counts to be sent */
+	Relation	relation;		/* rel that is using this entry */
+} PgStat_TableStatus;
+
+/* ----------
+ * PgStat_TableXactStatus		Per-table, per-subtransaction status
+ * ----------
+ */
+typedef struct PgStat_TableXactStatus
+{
+	PgStat_Counter tuples_inserted; /* tuples inserted in (sub)xact */
+	PgStat_Counter tuples_updated;	/* tuples updated in (sub)xact */
+	PgStat_Counter tuples_deleted;	/* tuples deleted in (sub)xact */
+	bool		truncdropped;	/* relation truncated/dropped in this
+								 * (sub)xact */
+	/* tuples i/u/d prior to truncate/drop */
+	PgStat_Counter inserted_pre_truncdrop;
+	PgStat_Counter updated_pre_truncdrop;
+	PgStat_Counter deleted_pre_truncdrop;
+	int			nest_level;		/* subtransaction nest level */
+	/* links to other structs for same relation: */
+	struct PgStat_TableXactStatus *upper;	/* next higher subxact if any */
+	PgStat_TableStatus *parent; /* per-table status */
+	/* structs of same subxact level are linked here: */
+	struct PgStat_TableXactStatus *next;	/* next of same subxact */
+} PgStat_TableXactStatus;
+
+
+/* ------------------------------------------------------------
+ * Data structures on disk and in shared memory follow
+ *
+ * PGSTAT_FILE_FORMAT_ID should be changed whenever any of these
+ * data structures change.
+ * ------------------------------------------------------------
+ */
+
+#define PGSTAT_FILE_FORMAT_ID	0x01A5BCA7
+
+typedef struct PgStat_ArchiverStats
+{
+	PgStat_Counter archived_count;	/* archival successes */
+	char		last_archived_wal[MAX_XFN_CHARS + 1];	/* last WAL file
+														 * archived */
+	TimestampTz last_archived_timestamp;	/* last archival success time */
+	PgStat_Counter failed_count;	/* failed archival attempts */
+	char		last_failed_wal[MAX_XFN_CHARS + 1]; /* WAL file involved in
+													 * last failure */
+	TimestampTz last_failed_timestamp;	/* last archival failure time */
+	TimestampTz stat_reset_timestamp;
+} PgStat_ArchiverStats;
+
+typedef struct PgStat_BgWriterStats
+{
+	PgStat_Counter buf_written_clean;
+	PgStat_Counter maxwritten_clean;
+	PgStat_Counter buf_alloc;
+	TimestampTz stat_reset_timestamp;
+} PgStat_BgWriterStats;
+
+typedef struct PgStat_CheckpointerStats
+{
+	PgStat_Counter timed_checkpoints;
+	PgStat_Counter requested_checkpoints;
+	PgStat_Counter checkpoint_write_time;	/* times in milliseconds */
+	PgStat_Counter checkpoint_sync_time;
+	PgStat_Counter buf_written_checkpoints;
+	PgStat_Counter buf_written_backend;
+	PgStat_Counter buf_fsync_backend;
+} PgStat_CheckpointerStats;
+
+typedef struct PgStat_StatDBEntry
+{
+	PgStat_Counter n_xact_commit;
+	PgStat_Counter n_xact_rollback;
+	PgStat_Counter n_blocks_fetched;
+	PgStat_Counter n_blocks_hit;
+	PgStat_Counter n_tuples_returned;
+	PgStat_Counter n_tuples_fetched;
+	PgStat_Counter n_tuples_inserted;
+	PgStat_Counter n_tuples_updated;
+	PgStat_Counter n_tuples_deleted;
+	TimestampTz last_autovac_time;
+	PgStat_Counter n_conflict_tablespace;
+	PgStat_Counter n_conflict_lock;
+	PgStat_Counter n_conflict_snapshot;
+	PgStat_Counter n_conflict_bufferpin;
+	PgStat_Counter n_conflict_startup_deadlock;
+	PgStat_Counter n_temp_files;
+	PgStat_Counter n_temp_bytes;
+	PgStat_Counter n_deadlocks;
+	PgStat_Counter n_checksum_failures;
+	TimestampTz last_checksum_failure;
+	PgStat_Counter n_block_read_time;	/* times in microseconds */
+	PgStat_Counter n_block_write_time;
+	PgStat_Counter n_sessions;
+	PgStat_Counter total_session_time;
+	PgStat_Counter total_active_time;
+	PgStat_Counter total_idle_in_xact_time;
+	PgStat_Counter n_sessions_abandoned;
+	PgStat_Counter n_sessions_fatal;
+	PgStat_Counter n_sessions_killed;
+
+	TimestampTz stat_reset_timestamp;
+} PgStat_StatDBEntry;
+
+typedef struct PgStat_StatFuncEntry
+{
+	PgStat_Counter f_numcalls;
+
+	PgStat_Counter f_total_time;	/* times in microseconds */
+	PgStat_Counter f_self_time;
+} PgStat_StatFuncEntry;
+
+typedef struct PgStat_StatReplSlotEntry
+{
+	/*
+	 * In PG 15 this field is unused, but not removed, to avoid changing
+	 * PGSTAT_FILE_FORMAT_ID.
+	 */
+	NameData	slotname_unused;
+	PgStat_Counter spill_txns;
+	PgStat_Counter spill_count;
+	PgStat_Counter spill_bytes;
+	PgStat_Counter stream_txns;
+	PgStat_Counter stream_count;
+	PgStat_Counter stream_bytes;
+	PgStat_Counter total_txns;
+	PgStat_Counter total_bytes;
+	TimestampTz stat_reset_timestamp;
+} PgStat_StatReplSlotEntry;
+
+typedef struct PgStat_SLRUStats
+{
+	PgStat_Counter blocks_zeroed;
+	PgStat_Counter blocks_hit;
+	PgStat_Counter blocks_read;
+	PgStat_Counter blocks_written;
+	PgStat_Counter blocks_exists;
+	PgStat_Counter flush;
+	PgStat_Counter truncate;
+	TimestampTz stat_reset_timestamp;
+} PgStat_SLRUStats;
+
+typedef struct PgStat_StatSubEntry
+{
+	PgStat_Counter apply_error_count;
+	PgStat_Counter sync_error_count;
+	TimestampTz stat_reset_timestamp;
+} PgStat_StatSubEntry;
+
+typedef struct PgStat_StatTabEntry
+{
+	PgStat_Counter numscans;
+
+	PgStat_Counter tuples_returned;
+	PgStat_Counter tuples_fetched;
+
+	PgStat_Counter tuples_inserted;
+	PgStat_Counter tuples_updated;
+	PgStat_Counter tuples_deleted;
+	PgStat_Counter tuples_hot_updated;
+
+	PgStat_Counter n_live_tuples;
+	PgStat_Counter n_dead_tuples;
+	PgStat_Counter changes_since_analyze;
+	PgStat_Counter inserts_since_vacuum;
+
+	PgStat_Counter blocks_fetched;
+	PgStat_Counter blocks_hit;
+
+	TimestampTz vacuum_timestamp;	/* user initiated vacuum */
+	PgStat_Counter vacuum_count;
+	TimestampTz autovac_vacuum_timestamp;	/* autovacuum initiated */
+	PgStat_Counter autovac_vacuum_count;
+	TimestampTz analyze_timestamp;	/* user initiated */
+	PgStat_Counter analyze_count;
+	TimestampTz autovac_analyze_timestamp;	/* autovacuum initiated */
+	PgStat_Counter autovac_analyze_count;
+} PgStat_StatTabEntry;
+
+typedef struct PgStat_WalStats
+{
+	PgStat_Counter wal_records;
+	PgStat_Counter wal_fpi;
+	uint64		wal_bytes;
+	PgStat_Counter wal_buffers_full;
+	PgStat_Counter wal_write;
+	PgStat_Counter wal_sync;
+	PgStat_Counter wal_write_time;
+	PgStat_Counter wal_sync_time;
+	TimestampTz stat_reset_timestamp;
+} PgStat_WalStats;
+
+
+/*
+ * Functions in pgstat.c
+ */
+
+/* functions called from postmaster */
+extern Size StatsShmemSize(void);
+extern void StatsShmemInit(void);
+
+/* Functions called during server startup / shutdown */
+extern void pgstat_restore_stats(void);
+extern void pgstat_discard_stats(void);
+extern void pgstat_before_server_shutdown(int code, Datum arg);
+
+/* Functions for backend initialization */
+extern void pgstat_initialize(void);
+
+/* Functions called from backends */
+extern long pgstat_report_stat(bool force);
+extern void pgstat_force_next_flush(void);
+
+extern void pgstat_reset_counters(void);
+extern void pgstat_reset(PgStat_Kind kind, Oid dboid, Oid objectid);
+extern void pgstat_reset_of_kind(PgStat_Kind kind);
+
+/* stats accessors */
+extern void pgstat_clear_snapshot(void);
+extern TimestampTz pgstat_get_stat_snapshot_timestamp(bool *have_snapshot);
+
+/* helpers */
+extern PgStat_Kind pgstat_get_kind_from_str(char *kind_str);
+extern bool pgstat_have_entry(PgStat_Kind kind, Oid dboid, Oid objoid);
+
+/* GUC hook for stats_fetch_consistency */
+extern void assign_stats_fetch_consistency(int newval, void *extra);
+
+/*
+ * Functions in pgstat_archiver.c
+ */
+
+extern void pgstat_report_archiver(const char *xlog, bool failed);
+extern PgStat_ArchiverStats *pgstat_fetch_stat_archiver(void);
+
+
+/*
+ * Functions in pgstat_bgwriter.c
+ */
+
+extern void pgstat_report_bgwriter(void);
+extern PgStat_BgWriterStats *pgstat_fetch_stat_bgwriter(void);
+
+
+/*
+ * Functions in pgstat_checkpointer.c
+ */
+
+extern void pgstat_report_checkpointer(void);
+extern PgStat_CheckpointerStats *pgstat_fetch_stat_checkpointer(void);
+
+
+/*
+ * Functions in pgstat_database.c
+ */
+
+extern void pgstat_drop_database(Oid databaseid);
+extern void pgstat_report_autovac(Oid dboid);
+extern void pgstat_report_recovery_conflict(int reason);
+extern void pgstat_report_deadlock(void);
+extern void pgstat_report_checksum_failures_in_db(Oid dboid, int failurecount);
+extern void pgstat_report_checksum_failure(void);
+extern void pgstat_report_connect(Oid dboid);
+
+#define pgstat_count_buffer_read_time(n)							\
+	(pgStatBlockReadTime += (n))
+#define pgstat_count_buffer_write_time(n)							\
+	(pgStatBlockWriteTime += (n))
+#define pgstat_count_conn_active_time(n)							\
+	(pgStatActiveTime += (n))
+#define pgstat_count_conn_txn_idle_time(n)							\
+	(pgStatTransactionIdleTime += (n))
+
+extern PgStat_StatDBEntry *pgstat_fetch_stat_dbentry(Oid dbid);
+
+/*
+ * Functions in pgstat_function.c
+ */
+
+extern void pgstat_create_function(Oid proid);
+extern void pgstat_drop_function(Oid proid);
+
+struct FunctionCallInfoBaseData;
+extern void pgstat_init_function_usage(struct FunctionCallInfoBaseData *fcinfo,
+									   PgStat_FunctionCallUsage *fcu);
+extern void pgstat_end_function_usage(PgStat_FunctionCallUsage *fcu,
+									  bool finalize);
+
+extern PgStat_StatFuncEntry *pgstat_fetch_stat_funcentry(Oid funcid);
+extern PgStat_BackendFunctionEntry *find_funcstat_entry(Oid func_id);
+
+
+/*
+ * Functions in pgstat_relation.c
+ */
+
+extern void pgstat_create_relation(Relation rel);
+extern void pgstat_drop_relation(Relation rel);
+extern void pgstat_copy_relation_stats(Relation dstrel, Relation srcrel);
+
+extern void pgstat_init_relation(Relation rel);
+extern void pgstat_assoc_relation(Relation rel);
+extern void pgstat_unlink_relation(Relation rel);
+
+extern void pgstat_report_vacuum(Oid tableoid, bool shared,
+								 PgStat_Counter livetuples, PgStat_Counter deadtuples);
+extern void pgstat_report_analyze(Relation rel,
+								  PgStat_Counter livetuples, PgStat_Counter deadtuples,
+								  bool resetcounter);
+
+/*
+ * If stats are enabled, but pending data hasn't been prepared yet, call
+ * pgstat_assoc_relation() to do so. See its comment for why this is done
+ * separately from pgstat_init_relation().
+ */
+#define pgstat_should_count_relation(rel)                           \
+	(likely((rel)->pgstat_info != NULL) ? true :                    \
+	 ((rel)->pgstat_enabled ? pgstat_assoc_relation(rel), true : false))
+
+/* nontransactional event counts are simple enough to inline */
+
+#define pgstat_count_heap_scan(rel)									\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_numscans++;				\
+	} while (0)
+#define pgstat_count_heap_getnext(rel)								\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_tuples_returned++;		\
+	} while (0)
+#define pgstat_count_heap_fetch(rel)								\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_tuples_fetched++;		\
+	} while (0)
+#define pgstat_count_index_scan(rel)								\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_numscans++;				\
+	} while (0)
+#define pgstat_count_index_tuples(rel, n)							\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_tuples_returned += (n);	\
+	} while (0)
+#define pgstat_count_buffer_read(rel)								\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_blocks_fetched++;		\
+	} while (0)
+#define pgstat_count_buffer_hit(rel)								\
+	do {															\
+		if (pgstat_should_count_relation(rel))						\
+			(rel)->pgstat_info->t_counts.t_blocks_hit++;			\
+	} while (0)
+
+extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
+extern void pgstat_count_heap_update(Relation rel, bool hot);
+extern void pgstat_count_heap_delete(Relation rel);
+extern void pgstat_count_truncate(Relation rel);
+extern void pgstat_update_heap_dead_tuples(Relation rel, int delta);
+
+extern void pgstat_twophase_postcommit(TransactionId xid, uint16 info,
+									   void *recdata, uint32 len);
+extern void pgstat_twophase_postabort(TransactionId xid, uint16 info,
+									  void *recdata, uint32 len);
+
+extern PgStat_StatTabEntry *pgstat_fetch_stat_tabentry(Oid relid);
+extern PgStat_StatTabEntry *pgstat_fetch_stat_tabentry_ext(bool shared,
+														   Oid relid);
+extern PgStat_TableStatus *find_tabstat_entry(Oid rel_id);
+
+
+/*
+ * Functions in pgstat_replslot.c
+ */
+
+extern void pgstat_reset_replslot(const char *name);
+struct ReplicationSlot;
+extern void pgstat_report_replslot(struct ReplicationSlot *slot, const PgStat_StatReplSlotEntry *repSlotStat);
+extern void pgstat_create_replslot(struct ReplicationSlot *slot);
+extern void pgstat_acquire_replslot(struct ReplicationSlot *slot);
+extern void pgstat_drop_replslot(struct ReplicationSlot *slot);
+extern PgStat_StatReplSlotEntry *pgstat_fetch_replslot(NameData slotname);
+
+
+/*
+ * Functions in pgstat_slru.c
+ */
+
+extern void pgstat_reset_slru(const char *);
+extern void pgstat_count_slru_page_zeroed(int slru_idx);
+extern void pgstat_count_slru_page_hit(int slru_idx);
+extern void pgstat_count_slru_page_read(int slru_idx);
+extern void pgstat_count_slru_page_written(int slru_idx);
+extern void pgstat_count_slru_page_exists(int slru_idx);
+extern void pgstat_count_slru_flush(int slru_idx);
+extern void pgstat_count_slru_truncate(int slru_idx);
+extern const char *pgstat_get_slru_name(int slru_idx);
+extern int	pgstat_get_slru_index(const char *name);
+extern PgStat_SLRUStats *pgstat_fetch_slru(void);
+
+
+/*
+ * Functions in pgstat_subscription.c
+ */
+
+extern void pgstat_report_subscription_error(Oid subid, bool is_apply_error);
+extern void pgstat_create_subscription(Oid subid);
+extern void pgstat_drop_subscription(Oid subid);
+extern PgStat_StatSubEntry *pgstat_fetch_stat_subscription(Oid subid);
+
+
+/*
+ * Functions in pgstat_xact.c
+ */
+
+extern void AtEOXact_PgStat(bool isCommit, bool parallel);
+extern void AtEOSubXact_PgStat(bool isCommit, int nestDepth);
+extern void AtPrepare_PgStat(void);
+extern void PostPrepare_PgStat(void);
+struct xl_xact_stats_item;
+extern int	pgstat_get_transactional_drops(bool isCommit, struct xl_xact_stats_item **items);
+extern void pgstat_execute_transactional_drops(int ndrops, struct xl_xact_stats_item *items, bool is_redo);
+
+
+/*
+ * Functions in pgstat_wal.c
+ */
+
+extern void pgstat_report_wal(bool force);
+extern PgStat_WalStats *pgstat_fetch_stat_wal(void);
+
+
+/*
+ * Variables in pgstat.c
+ */
+
+/* GUC parameters */
+extern PGDLLIMPORT bool pgstat_track_counts;
+extern PGDLLIMPORT int pgstat_track_functions;
+extern PGDLLIMPORT int pgstat_fetch_consistency;
+
+
+/*
+ * Variables in pgstat_bgwriter.c
+ */
+
+/* updated directly by bgwriter and bufmgr */
+extern PGDLLIMPORT PgStat_BgWriterStats PendingBgWriterStats;
+
+
+/*
+ * Variables in pgstat_checkpointer.c
+ */
+
+/*
+ * Checkpointer statistics counters are updated directly by checkpointer and
+ * bufmgr.
+ */
+extern PGDLLIMPORT PgStat_CheckpointerStats PendingCheckpointerStats;
+
+
+/*
+ * Variables in pgstat_database.c
+ */
+
+/* Updated by pgstat_count_buffer_*_time macros */
+extern PGDLLIMPORT PgStat_Counter pgStatBlockReadTime;
+extern PGDLLIMPORT PgStat_Counter pgStatBlockWriteTime;
+
+/*
+ * Updated by pgstat_count_conn_*_time macros, called by
+ * pgstat_report_activity().
+ */
+extern PGDLLIMPORT PgStat_Counter pgStatActiveTime;
+extern PGDLLIMPORT PgStat_Counter pgStatTransactionIdleTime;
+
+/* updated by the traffic cop and in errfinish() */
+extern PGDLLIMPORT SessionEndType pgStatSessionEndCause;
+
+
+/*
+ * Variables in pgstat_wal.c
+ */
+
+/* updated directly by backends and background processes */
+extern PGDLLIMPORT PgStat_WalStats PendingWalStats;
+
+
+#endif							/* PGSTAT_H */