diff options
Diffstat (limited to 'src/backend/utils/adt/pgstatfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/pgstatfuncs.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c index 924698e6ae4..9d707c35216 100644 --- a/src/backend/utils/adt/pgstatfuncs.c +++ b/src/backend/utils/adt/pgstatfuncs.c @@ -1246,6 +1246,147 @@ pg_stat_get_buf_alloc(PG_FUNCTION_ARGS) } /* +* When adding a new column to the pg_stat_io view, add a new enum value +* here above IO_NUM_COLUMNS. +*/ +typedef enum io_stat_col +{ + IO_COL_BACKEND_TYPE, + IO_COL_IO_OBJECT, + IO_COL_IO_CONTEXT, + IO_COL_READS, + IO_COL_WRITES, + IO_COL_EXTENDS, + IO_COL_CONVERSION, + IO_COL_EVICTIONS, + IO_COL_REUSES, + IO_COL_FSYNCS, + IO_COL_RESET_TIME, + IO_NUM_COLUMNS, +} io_stat_col; + +/* + * When adding a new IOOp, add a new io_stat_col and add a case to this + * function returning the corresponding io_stat_col. + */ +static io_stat_col +pgstat_get_io_op_index(IOOp io_op) +{ + switch (io_op) + { + case IOOP_EVICT: + return IO_COL_EVICTIONS; + case IOOP_READ: + return IO_COL_READS; + case IOOP_REUSE: + return IO_COL_REUSES; + case IOOP_WRITE: + return IO_COL_WRITES; + case IOOP_EXTEND: + return IO_COL_EXTENDS; + case IOOP_FSYNC: + return IO_COL_FSYNCS; + } + + elog(ERROR, "unrecognized IOOp value: %d", io_op); + pg_unreachable(); +} + +Datum +pg_stat_get_io(PG_FUNCTION_ARGS) +{ + ReturnSetInfo *rsinfo; + PgStat_IO *backends_io_stats; + Datum reset_time; + + InitMaterializedSRF(fcinfo, 0); + rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; + + backends_io_stats = pgstat_fetch_stat_io(); + + reset_time = TimestampTzGetDatum(backends_io_stats->stat_reset_timestamp); + + for (BackendType bktype = B_INVALID; bktype < BACKEND_NUM_TYPES; bktype++) + { + Datum bktype_desc = CStringGetTextDatum(GetBackendTypeDesc(bktype)); + PgStat_BktypeIO *bktype_stats = &backends_io_stats->stats[bktype]; + + /* + * In Assert builds, we can afford an extra loop through all of the + * counters checking that only expected stats are non-zero, since it + * keeps the non-Assert code cleaner. + */ + Assert(pgstat_bktype_io_stats_valid(bktype_stats, bktype)); + + /* + * For those BackendTypes without IO Operation stats, skip + * representing them in the view altogether. + */ + if (!pgstat_tracks_io_bktype(bktype)) + continue; + + for (IOObject io_obj = IOOBJECT_FIRST; + io_obj < IOOBJECT_NUM_TYPES; io_obj++) + { + const char *obj_name = pgstat_get_io_object_name(io_obj); + + for (IOContext io_context = IOCONTEXT_FIRST; + io_context < IOCONTEXT_NUM_TYPES; io_context++) + { + const char *context_name = pgstat_get_io_context_name(io_context); + + Datum values[IO_NUM_COLUMNS] = {0}; + bool nulls[IO_NUM_COLUMNS] = {0}; + + /* + * Some combinations of BackendType, IOObject, and IOContext + * are not valid for any type of IOOp. In such cases, omit the + * entire row from the view. + */ + if (!pgstat_tracks_io_object(bktype, io_obj, io_context)) + continue; + + values[IO_COL_BACKEND_TYPE] = bktype_desc; + values[IO_COL_IO_CONTEXT] = CStringGetTextDatum(context_name); + values[IO_COL_IO_OBJECT] = CStringGetTextDatum(obj_name); + values[IO_COL_RESET_TIME] = TimestampTzGetDatum(reset_time); + + /* + * Hard-code this to the value of BLCKSZ for now. Future + * values could include XLOG_BLCKSZ, once WAL IO is tracked, + * and constant multipliers, once non-block-oriented IO (e.g. + * temporary file IO) is tracked. + */ + values[IO_COL_CONVERSION] = Int64GetDatum(BLCKSZ); + + for (IOOp io_op = IOOP_FIRST; io_op < IOOP_NUM_TYPES; io_op++) + { + int col_idx = pgstat_get_io_op_index(io_op); + + /* + * Some combinations of BackendType and IOOp, of IOContext + * and IOOp, and of IOObject and IOOp are not tracked. Set + * these cells in the view NULL. + */ + nulls[col_idx] = !pgstat_tracks_io_op(bktype, io_obj, io_context, io_op); + + if (nulls[col_idx]) + continue; + + values[col_idx] = + Int64GetDatum(bktype_stats->data[io_obj][io_context][io_op]); + } + + tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, + values, nulls); + } + } + } + + return (Datum) 0; +} + +/* * Returns statistics of WAL activity */ Datum |