From ea3b9053f84d5b436fe533187165637733e8fd5c Mon Sep 17 00:00:00 2001 From: Amit Kapila Date: Thu, 9 Jul 2020 10:16:44 +0530 Subject: [PATCH] Revert "Track statistics for spilling of changes from ReorderBuffer". The stats with this commit was available only for WALSenders, however, users might want to see for backends doing logical decoding via SQL API. Then, users might want to reset and access these stats across server restart which was not possible with the current patch. List of commits reverted: caa3c4242c Don't call elog() while holding spinlock. e641b2a995 Doc: Update the documentation for spilled transaction statistics. 5883f5fe27 Fix unportable printf format introduced in commit 9290ad198. 9290ad198b Track statistics for spilling of changes from ReorderBuffer. Backpatch-through: 13, where it was introduced Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com --- doc/src/sgml/monitoring.sgml | 41 ----------------------- src/backend/catalog/system_views.sql | 5 +-- src/backend/replication/logical/reorderbuffer.c | 12 ------- src/backend/replication/walsender.c | 43 ++----------------------- src/include/catalog/pg_proc.dat | 6 ++-- src/include/replication/reorderbuffer.h | 11 ------- src/include/replication/walsender_private.h | 5 --- src/test/regress/expected/rules.out | 7 ++-- 8 files changed, 8 insertions(+), 122 deletions(-) diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml index f7ef4ba..a56d7fe 100644 --- a/doc/src/sgml/monitoring.sgml +++ b/doc/src/sgml/monitoring.sgml @@ -2467,41 +2467,6 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i - - - spill_txns bigint - - - Number of transactions spilled to disk after the memory used by - logical decoding exceeds logical_decoding_work_mem. The - counter gets incremented both for top-level transactions and - subtransactions. - - - - - - spill_count bigint - - - Number of times transactions were spilled to disk. Transactions - may get spilled repeatedly, and this counter gets incremented on every - such invocation. - - - - - - spill_bytes bigint - - - Amount of decoded transaction data spilled to disk. - - - - - - The lag times reported in the pg_stat_replication view are measurements of the time taken for recent WAL to be written, @@ -2522,12 +2487,6 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i mechanism will simply display NULL lag. - - Tracking of spilled transactions works only for logical replication. In - physical replication, the tracking mechanism will display 0 for spilled - statistics. - - The reported lag times are not predictions of how long it will take for diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql index 73676d0..b6d35c2 100644 --- a/src/backend/catalog/system_views.sql +++ b/src/backend/catalog/system_views.sql @@ -785,10 +785,7 @@ CREATE VIEW pg_stat_replication AS W.replay_lag, W.sync_priority, W.sync_state, - W.reply_time, - W.spill_txns, - W.spill_count, - W.spill_bytes + W.reply_time FROM pg_stat_get_activity(NULL) AS S JOIN pg_stat_get_wal_senders() AS W ON (S.pid = W.pid) LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid); diff --git a/src/backend/replication/logical/reorderbuffer.c b/src/backend/replication/logical/reorderbuffer.c index 7afa227..5251932 100644 --- a/src/backend/replication/logical/reorderbuffer.c +++ b/src/backend/replication/logical/reorderbuffer.c @@ -317,10 +317,6 @@ ReorderBufferAllocate(void) buffer->outbufsize = 0; buffer->size = 0; - buffer->spillCount = 0; - buffer->spillTxns = 0; - buffer->spillBytes = 0; - buffer->current_restart_decoding_lsn = InvalidXLogRecPtr; dlist_init(&buffer->toplevel_by_lsn); @@ -2418,7 +2414,6 @@ ReorderBufferSerializeTXN(ReorderBuffer *rb, ReorderBufferTXN *txn) int fd = -1; XLogSegNo curOpenSegNo = 0; Size spilled = 0; - Size size = txn->size; elog(DEBUG2, "spill %u changes in XID %u to disk", (uint32) txn->nentries_mem, txn->xid); @@ -2477,13 +2472,6 @@ ReorderBufferSerializeTXN(ReorderBuffer *rb, ReorderBufferTXN *txn) spilled++; } - /* update the statistics */ - rb->spillCount += 1; - rb->spillBytes += size; - - /* Don't consider already serialized transactions. */ - rb->spillTxns += rbtxn_is_serialized(txn) ? 0 : 1; - Assert(spilled == txn->nentries_mem); Assert(dlist_is_empty(&txn->changes)); txn->nentries_mem = 0; diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index f66acb8..5e2210d 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -254,7 +254,6 @@ static bool TransactionIdInRecentPast(TransactionId xid, uint32 epoch); static void WalSndSegmentOpen(XLogReaderState *state, XLogSegNo nextSegNo, TimeLineID *tli_p); -static void UpdateSpillStats(LogicalDecodingContext *ctx); /* Initialize walsender process before entering the main command loop */ @@ -1348,8 +1347,7 @@ WalSndWriteData(LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId xid, /* * LogicalDecodingContext 'update_progress' callback. * - * Write the current position to the lag tracker (see XLogSendPhysical), - * and update the spill statistics. + * Write the current position to the lag tracker (see XLogSendPhysical). */ static void WalSndUpdateProgress(LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId xid) @@ -1368,11 +1366,6 @@ WalSndUpdateProgress(LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId LagTrackerWrite(lsn, now); sendTime = now; - - /* - * Update statistics about transactions that spilled to disk. - */ - UpdateSpillStats(ctx); } /* @@ -2418,9 +2411,6 @@ InitWalSenderSlot(void) walsnd->sync_standby_priority = 0; walsnd->latch = &MyProc->procLatch; walsnd->replyTime = 0; - walsnd->spillTxns = 0; - walsnd->spillCount = 0; - walsnd->spillBytes = 0; SpinLockRelease(&walsnd->mutex); /* don't need the lock anymore */ MyWalSnd = (WalSnd *) walsnd; @@ -3256,7 +3246,7 @@ offset_to_interval(TimeOffset offset) Datum pg_stat_get_wal_senders(PG_FUNCTION_ARGS) { -#define PG_STAT_GET_WAL_SENDERS_COLS 15 +#define PG_STAT_GET_WAL_SENDERS_COLS 12 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; TupleDesc tupdesc; Tuplestorestate *tupstore; @@ -3310,9 +3300,6 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS) int pid; WalSndState state; TimestampTz replyTime; - int64 spillTxns; - int64 spillCount; - int64 spillBytes; bool is_sync_standby; Datum values[PG_STAT_GET_WAL_SENDERS_COLS]; bool nulls[PG_STAT_GET_WAL_SENDERS_COLS]; @@ -3336,9 +3323,6 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS) applyLag = walsnd->applyLag; priority = walsnd->sync_standby_priority; replyTime = walsnd->replyTime; - spillTxns = walsnd->spillTxns; - spillCount = walsnd->spillCount; - spillBytes = walsnd->spillBytes; SpinLockRelease(&walsnd->mutex); /* @@ -3436,11 +3420,6 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS) nulls[11] = true; else values[11] = TimestampTzGetDatum(replyTime); - - /* spill to disk */ - values[12] = Int64GetDatum(spillTxns); - values[13] = Int64GetDatum(spillCount); - values[14] = Int64GetDatum(spillBytes); } tuplestore_putvalues(tupstore, tupdesc, values, nulls); @@ -3677,21 +3656,3 @@ LagTrackerRead(int head, XLogRecPtr lsn, TimestampTz now) Assert(time != 0); return now - time; } - -static void -UpdateSpillStats(LogicalDecodingContext *ctx) -{ - ReorderBuffer *rb = ctx->reorder; - - elog(DEBUG2, "UpdateSpillStats: updating stats %p %lld %lld %lld", - rb, - (long long) rb->spillTxns, - (long long) rb->spillCount, - (long long) rb->spillBytes); - - SpinLockAcquire(&MyWalSnd->mutex); - MyWalSnd->spillTxns = rb->spillTxns; - MyWalSnd->spillCount = rb->spillCount; - MyWalSnd->spillBytes = rb->spillBytes; - SpinLockRelease(&MyWalSnd->mutex); -} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index d951b4a..7d3cf73 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -5240,9 +5240,9 @@ proname => 'pg_stat_get_wal_senders', prorows => '10', proisstrict => 'f', proretset => 't', provolatile => 's', proparallel => 'r', prorettype => 'record', proargtypes => '', - proallargtypes => '{int4,text,pg_lsn,pg_lsn,pg_lsn,pg_lsn,interval,interval,interval,int4,text,timestamptz,int8,int8,int8}', - proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}', - proargnames => '{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state,reply_time,spill_txns,spill_count,spill_bytes}', + proallargtypes => '{int4,text,pg_lsn,pg_lsn,pg_lsn,pg_lsn,interval,interval,interval,int4,text,timestamptz}', + proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o}', + proargnames => '{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state,reply_time}', prosrc => 'pg_stat_get_wal_senders' }, { oid => '3317', descr => 'statistics: information about WAL receiver', proname => 'pg_stat_get_wal_receiver', proisstrict => 'f', provolatile => 's', diff --git a/src/include/replication/reorderbuffer.h b/src/include/replication/reorderbuffer.h index 626ecf4..019bd38 100644 --- a/src/include/replication/reorderbuffer.h +++ b/src/include/replication/reorderbuffer.h @@ -413,17 +413,6 @@ struct ReorderBuffer /* memory accounting */ Size size; - - /* - * Statistics about transactions spilled to disk. - * - * A single transaction may be spilled repeatedly, which is why we keep - * two different counters. For spilling, the transaction counter includes - * both toplevel transactions and subtransactions. - */ - int64 spillCount; /* spill-to-disk invocation counter */ - int64 spillTxns; /* number of transactions spilled to disk */ - int64 spillBytes; /* amount of data spilled to disk */ }; diff --git a/src/include/replication/walsender_private.h b/src/include/replication/walsender_private.h index 734acec..509856c 100644 --- a/src/include/replication/walsender_private.h +++ b/src/include/replication/walsender_private.h @@ -78,11 +78,6 @@ typedef struct WalSnd * Timestamp of the last message received from standby. */ TimestampTz replyTime; - - /* Statistics for transactions spilled to disk. */ - int64 spillTxns; - int64 spillCount; - int64 spillBytes; } WalSnd; extern WalSnd *MyWalSnd; diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out index 93bb215..fa436f2 100644 --- a/src/test/regress/expected/rules.out +++ b/src/test/regress/expected/rules.out @@ -2002,12 +2002,9 @@ pg_stat_replication| SELECT s.pid, w.replay_lag, w.sync_priority, w.sync_state, - w.reply_time, - w.spill_txns, - w.spill_count, - w.spill_bytes + w.reply_time FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid) - JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time, spill_txns, spill_count, spill_bytes) ON ((s.pid = w.pid))) + JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid))) LEFT JOIN pg_authid u ON ((s.usesysid = u.oid))); pg_stat_slru| SELECT s.name, s.blks_zeroed, -- 1.8.3.1