Re: WAL segments pile up during standalone mode
Bruce Momjian <bruce@momjian.us>
From: Bruce Momjian <bruce@momjian.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Alvaro Herrera <alvherre@commandprompt.com>, Robert Haas <robertmhaas@gmail.com>, Fujii Masao <masao.fujii@gmail.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2011-03-10T01:21:04Z
Lists: pgsql-hackers
Attachments
- /rtmp/checkpoint.diff (text/x-diff) patch
Tom Lane wrote: > Alvaro Herrera <alvherre@commandprompt.com> writes: > > I admit I have no idea why these guys seem to run into wraparound > > problems so much. > > > On the other hand, I'm not sure that it would work to try to checkpoint > > "during" vacuum, because the backend is in a transaction. Maybe it > > would work to force a checkpoint after each command, and between tables > > in a multi-table vacuum (which is presumably a common thing to do in a > > standalone backend) or something like that? > > I really don't care for the idea of standalone mode doing *anything* > the user didn't explicitly tell it to. In its role as a disaster > recovery tool, that's just a recipe for shooting yourself in the foot. > > Perhaps this problem would be adequately addressed by documentation, > ie suggest that when vacuuming very large tables in standalone mode, > you should issue CHECKPOINT after each one. I documented that there is no automatic background processing (checkpoints) in single-user mode. I did not mention the idea of running checkpoints manually. Applied patch attached. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. +