From f35ebd2aa1a2c5d99e859abed488b67c4e3694ff Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 11 May 2012 18:33:39 -0400 Subject: [PATCH] Update example of process titles shown by "ps". This example was quite old: it lacked the WAL writer and autovac launcher as well as the more recently added checkpointer. Linux "ps" seems to show slightly different stuff now too. --- doc/src/sgml/monitoring.sgml | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml index b27c686130..830f6217d2 100644 --- a/doc/src/sgml/monitoring.sgml +++ b/doc/src/sgml/monitoring.sgml @@ -48,23 +48,27 @@ $ ps auxww | grep ^postgres -postgres 960 0.0 1.1 6104 1480 pts/1 SN 13:17 0:00 postgres -i -postgres 963 0.0 1.1 7084 1472 pts/1 SN 13:17 0:00 postgres: writer process -postgres 965 0.0 1.1 6152 1512 pts/1 SN 13:17 0:00 postgres: stats collector process -postgres 998 0.0 2.3 6532 2992 pts/1 SN 13:18 0:00 postgres: tgl runbug 127.0.0.1 idle -postgres 1003 0.0 2.4 6532 3128 pts/1 SN 13:19 0:00 postgres: tgl regression [local] SELECT waiting -postgres 1016 0.1 2.4 6532 3080 pts/1 SN 13:19 0:00 postgres: tgl regression [local] idle in transaction +postgres 15551 0.0 0.1 57536 7132 pts/0 S 18:02 0:00 postgres -i +postgres 15554 0.0 0.0 57536 1184 ? Ss 18:02 0:00 postgres: writer process +postgres 15555 0.0 0.0 57536 916 ? Ss 18:02 0:00 postgres: checkpointer process +postgres 15556 0.0 0.0 57536 916 ? Ss 18:02 0:00 postgres: wal writer process +postgres 15557 0.0 0.0 58504 2244 ? Ss 18:02 0:00 postgres: autovacuum launcher process +postgres 15558 0.0 0.0 17512 1068 ? Ss 18:02 0:00 postgres: stats collector process +postgres 15582 0.0 0.0 58772 3080 ? Ss 18:04 0:00 postgres: joe runbug 127.0.0.1 idle +postgres 15606 0.0 0.0 58772 3052 ? Ss 18:07 0:00 postgres: tgl regression [local] SELECT waiting +postgres 15610 0.0 0.0 58772 3056 ? Ss 18:07 0:00 postgres: tgl regression [local] idle in transaction (The appropriate invocation of ps varies across different platforms, as do the details of what is shown. This example is from a recent Linux system.) The first process listed here is the master server process. The command arguments - shown for it are the same ones used when it was launched. The next two + shown for it are the same ones used when it was launched. The next five processes are background worker processes automatically launched by the master process. (The stats collector process will not be present - if you have set - the system not to start the statistics collector.) Each of the remaining + if you have set the system not to start the statistics collector; likewise + the autovacuum launcher process can be disabled.) + Each of the remaining processes is a server process handling one client connection. Each such process sets its command line display in the form @@ -79,8 +83,12 @@ postgres: user database host SELECT. Also, waiting is appended if the server process is presently waiting on a lock held by another session. In the above example we can infer - that process 1003 is waiting for process 1016 to complete its transaction and - thereby release some lock. + that process 15606 is waiting for process 15610 to complete its transaction + and thereby release some lock. (Process 15610 must be the blocker, because + there is no other active session. In more complicated cases it would be + necessary to look into the + pg_locks + system view to determine who is blocking whom.) -- 2.40.0