For a documentation patch should this not be back ported to all relevant versions?
On 8/21/10, Bruce Momjian <br...@momjian.us> wrote: > Josh Berkus wrote: >> >> > On further reflection, though: since we put in the BufferAccessStrategy >> > code, which was in 8.3, the background writer isn't *supposed* to be >> > very much involved in writing pages that are dirtied by VACUUM. VACUUM >> > runs in a small ring of buffers and is supposed to have to clean its own >> > dirt most of the time. So it's wrong to blame this on the bgwriter not >> > holding up its end. Rather, what you need to be thinking about is how >> > come vacuum seems to be making lots of pages dirty on only one of these >> > machines. >> >> This is an anti-wraparound vacuum, so it could have something to do with >> the hint bits. Maybe it's setting the freeze bit on every page, and >> writing them one page at a time? Still don't understand the call to >> pollsys, even so, though. > > We often mention that we do vacuum freeze for anti-wraparound vacuum, > but not for pg_clog file removal, which is the primary trigger for > autovacuum vacuum freezing. I have added the attached documentation > patch for autovacuum_freeze_max_age; back-patched to 9.0. > > -- > Bruce Momjian <br...@momjian.us> http://momjian.us > EnterpriseDB http://enterprisedb.com > > + It's impossible for everything to be true. + > -- Rob Wultsch wult...@gmail.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
