Re: Return of the Solaris vacuum polling problem -- anyone remember this?
Alvaro Herrera <alvherre@commandprompt.com>
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Bruce Momjian <bruce@momjian.us>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Josh Berkus <josh@agliodbs.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2010-08-23T16:14:52Z
Lists: pgsql-hackers
Excerpts from Bruce Momjian's message of dom ago 22 12:51:47 -0400 2010: > Well, the reason that value is 200 million is for pg_clog cleanup, not > for xid wraparound protection. The next sentence does relate to xid > wraparound, but it seems to fit because the previous sentence ends with > xid wraparound: > > Note that the system will launch autovacuum processes to > prevent wraparound even when autovacuum is otherwise disabled. > > If we were worried about just xid wraparound I assume the value would be > 2 billion. > > Do you have a suggestion? Reorder the items? I'd add another para before that one saying that this value "also" affects pg_clog truncation. I agree that putting pg_clog truncation as the first item here is not an improvement. For most people, having those pg_clog files there or not is going to be a wash, compared to data size. -- Álvaro Herrera <alvherre@commandprompt.com> The PostgreSQL Company - Command Prompt, Inc. PostgreSQL Replication, Consulting, Custom Development, 24x7 support