pg.ddx.io pgsql-admin@postgresql.org mailing list archive
help / color / mirror / Atom feedAutovacuum progressing slow (with high activity on the system).
2+ messages / 2 participants
[nested] [flat]
* Autovacuum progressing slow (with high activity on the system).
@ 2014-02-04 13:38 jesper@krogh.cc
0 siblings, 1 reply; 2+ messages in thread
From: jesper@krogh.cc @ 2014-02-04 13:38 UTC (permalink / raw)
To: pgsql-admin
Hi.
The database is a large database (3TB+) and I have 200+ backend
processes polling a message queuetable for work to do. On this message
queue table, when activity rises autovacuum fails to make progress and I
cannot get what is actually holding it back:
Stracing the process gives this pattern: (strace -T -p <pid of autovacuum>):
....
semop(18317336, {{1, 1, 0}}, 1) = 0 <0.000021>
semop(19562558, {{10, -1, 0}}, 1) = 0 <141.819414>
lseek(156, 566099968, SEEK_SET) = 566099968 <0.000015>
read(156, "\233\230\0\0`\226\347\332\1\0\0\0\260\3\220\21\360\37\4
\0\0\0\0\340\237 \0\220\221 \0"..., 8192) = 8192 <0.000027>
...
read(156, "\234\230\0\0\210hx\240\1\0\0\0\350\4\260\f\360\37\4
\0\0\0\0\340\237 \0\260\214 \0"..., 8192) = 8192 <0.000018>
semop(19562558, {{10, -1, 0}}, 1) = 0 <32.707159>
lseek(30, 706174976, SEEK_SET) = 706174976 <0.000025>
write(30, "\235\230\0\0\240\353\25v\1\0\0\0\30\0\370\37\370\37\4 \
...
In other words .. large "sleeps" on semops on this semop(19562558, {{10,
-1, 0}}, 1)" .. thus no progress while waiting for this lock. If I pick
the
pg_locks view at the same time, it does not show that is is waiting for
anything.
Can I somehow get deeper into what competing activity that causes
autovacuum to fail making progress?
Thanks.
Jesper
--
Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-admin
^ permalink raw reply [nested|flat] 2+ messages in thread
* Re: Autovacuum progressing slow (with high activity on the system).
@ 2014-02-28 21:39 Kevin Grittner <kgrittn@ymail.com>
parent: jesper@krogh.cc
0 siblings, 0 replies; 2+ messages in thread
From: Kevin Grittner @ 2014-02-28 21:39 UTC (permalink / raw)
To: jesper@krogh.cc <jesper@krogh.cc>; pgsql-admin
"jesper@krogh.cc" <jesper@krogh.cc> wrote:
> The database is a large database (3TB+) and I have 200+ backend
> processes polling a message queuetable for work to do. On this message
> queue table, when activity rises autovacuum fails to make progress and I
> cannot get what is actually holding it back
What version is this, as shown by the version() function?
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
--
Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-admin
^ permalink raw reply [nested|flat] 2+ messages in thread
end of thread, other threads:[~2014-02-28 21:39 UTC | newest]
Thread overview: 2+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2014-02-04 13:38 Autovacuum progressing slow (with high activity on the system). jesper@krogh.cc
2014-02-28 21:39 ` Kevin Grittner <kgrittn@ymail.com>
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox