3 files changed, 101 insertions, 1 deletions

diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 96b3a1e1a07..c309e0233d6 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -332,6 +332,8 @@ typedef enum BackendType
 	B_WAL_WRITER,
 } BackendType;
 
+#define BACKEND_NUM_TYPES (B_WAL_WRITER + 1)
+
 extern PGDLLIMPORT BackendType MyBackendType;
 
 extern const char *GetBackendTypeDesc(BackendType backendType);
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 5e3326a3b91..db9675884f3 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -48,6 +48,7 @@ typedef enum PgStat_Kind
 	PGSTAT_KIND_ARCHIVER,
 	PGSTAT_KIND_BGWRITER,
 	PGSTAT_KIND_CHECKPOINTER,
+	PGSTAT_KIND_IO,
 	PGSTAT_KIND_SLRU,
 	PGSTAT_KIND_WAL,
 } PgStat_Kind;
@@ -242,7 +243,7 @@ typedef struct PgStat_TableXactStatus
  * ------------------------------------------------------------
  */
 
-#define PGSTAT_FILE_FORMAT_ID	0x01A5BCA9
+#define PGSTAT_FILE_FORMAT_ID	0x01A5BCAA
 
 typedef struct PgStat_ArchiverStats
 {
@@ -276,6 +277,55 @@ typedef struct PgStat_CheckpointerStats
 	PgStat_Counter buf_fsync_backend;
 } PgStat_CheckpointerStats;
 
+
+/*
+ * Types related to counting IO operations
+ */
+typedef enum IOObject
+{
+	IOOBJECT_RELATION,
+	IOOBJECT_TEMP_RELATION,
+} IOObject;
+
+#define IOOBJECT_FIRST IOOBJECT_RELATION
+#define IOOBJECT_NUM_TYPES (IOOBJECT_TEMP_RELATION + 1)
+
+typedef enum IOContext
+{
+	IOCONTEXT_BULKREAD,
+	IOCONTEXT_BULKWRITE,
+	IOCONTEXT_NORMAL,
+	IOCONTEXT_VACUUM,
+} IOContext;
+
+#define IOCONTEXT_FIRST IOCONTEXT_BULKREAD
+#define IOCONTEXT_NUM_TYPES (IOCONTEXT_VACUUM + 1)
+
+typedef enum IOOp
+{
+	IOOP_EVICT,
+	IOOP_EXTEND,
+	IOOP_FSYNC,
+	IOOP_READ,
+	IOOP_REUSE,
+	IOOP_WRITE,
+} IOOp;
+
+#define IOOP_FIRST IOOP_EVICT
+#define IOOP_NUM_TYPES (IOOP_WRITE + 1)
+
+typedef struct PgStat_BktypeIO
+{
+	PgStat_Counter data[IOOBJECT_NUM_TYPES][IOCONTEXT_NUM_TYPES][IOOP_NUM_TYPES];
+} PgStat_BktypeIO;
+
+typedef struct PgStat_IO
+{
+	TimestampTz stat_reset_timestamp;
+	PgStat_BktypeIO stats[BACKEND_NUM_TYPES];
+} PgStat_IO;
+
+
 typedef struct PgStat_StatDBEntry
 {
 	PgStat_Counter xact_commit;
@@ -454,6 +504,24 @@ extern PgStat_CheckpointerStats *pgstat_fetch_stat_checkpointer(void);
 
 
 /*
+ * Functions in pgstat_io.c
+ */
+
+extern bool pgstat_bktype_io_stats_valid(PgStat_BktypeIO *context_ops,
+										 BackendType bktype);
+extern void pgstat_count_io_op(IOObject io_object, IOContext io_context, IOOp io_op);
+extern PgStat_IO *pgstat_fetch_stat_io(void);
+extern const char *pgstat_get_io_context_name(IOContext io_context);
+extern const char *pgstat_get_io_object_name(IOObject io_object);
+
+extern bool pgstat_tracks_io_bktype(BackendType bktype);
+extern bool pgstat_tracks_io_object(BackendType bktype,
+									IOObject io_object, IOContext io_context);
+extern bool pgstat_tracks_io_op(BackendType bktype, IOObject io_object,
+								IOContext io_context, IOOp io_op);
+
+
+/*
  * Functions in pgstat_database.c
  */
 
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index 12fd51f1ae3..6badb2fde4b 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -329,6 +329,17 @@ typedef struct PgStatShared_Checkpointer
 	PgStat_CheckpointerStats reset_offset;
 } PgStatShared_Checkpointer;
 
+/* Shared-memory ready PgStat_IO */
+typedef struct PgStatShared_IO
+{
+	/*
+	 * locks[i] protects stats.stats[i]. locks[0] also protects
+	 * stats.stat_reset_timestamp.
+	 */
+	LWLock		locks[BACKEND_NUM_TYPES];
+	PgStat_IO	stats;
+} PgStatShared_IO;
+
 typedef struct PgStatShared_SLRU
 {
 	/* lock protects ->stats */
@@ -419,6 +430,7 @@ typedef struct PgStat_ShmemControl
 	PgStatShared_Archiver archiver;
 	PgStatShared_BgWriter bgwriter;
 	PgStatShared_Checkpointer checkpointer;
+	PgStatShared_IO io;
 	PgStatShared_SLRU slru;
 	PgStatShared_Wal wal;
 } PgStat_ShmemControl;
@@ -442,6 +454,8 @@ typedef struct PgStat_Snapshot
 
 	PgStat_CheckpointerStats checkpointer;
 
+	PgStat_IO	io;
+
 	PgStat_SLRUStats slru[SLRU_NUM_ELEMENTS];
 
 	PgStat_WalStats wal;
@@ -550,6 +564,15 @@ extern bool pgstat_function_flush_cb(PgStat_EntryRef *entry_ref, bool nowait);
 
 
 /*
+ * Functions in pgstat_io.c
+ */
+
+extern bool pgstat_flush_io(bool nowait);
+extern void pgstat_io_reset_all_cb(TimestampTz ts);
+extern void pgstat_io_snapshot_cb(void);
+
+
+/*
  * Functions in pgstat_relation.c
  */
 
@@ -644,6 +667,13 @@ extern PGDLLIMPORT PgStat_LocalState pgStatLocal;
 
 
 /*
+ * Variables in pgstat_io.c
+ */
+
+extern PGDLLIMPORT bool have_iostats;
+
+
+/*
  * Variables in pgstat_slru.c
  */