Hello! On Fri, 6 Sep 2002, Christopher Kings-Lynne wrote:
> This question should not be posted to -patches, changed accordingly. > > What happens if you go 'VACUUM VERBOSE FULL goods;'? Oh, big thanx! But 'VACUUM VERBOSE FULL goods;' didn't work, only 'VACUUM FULL VERBOSE goods;' did.:) I make a guess I've got this due to parallel running of a program making bulk INSERTs/UPDATEs into that table. Mmm...I need a way to avoid the big number of unused pages in such a case. LOCK TABLE? > > Your on-disk files won't shrink or have unused tuples removed unless you > VACUUM FULL. The problem with doing VACUUM FULL is that it totally locks > the whole table while it's running, meaning no-one can use the table. This This can't scare people whom had dealt with 6.x.;) Only if "We scare because we care"...=) > is bad in production environments, so it's not the default. Bear in mind > that postgres will re-use the unused portion of the table as you add new > tuples... Yes, as an ole MUMPSter I did catch this very well some times ago.=) > > Chris > > > Some time ago I've got troubles with performance of my PG. > > After investigation I had found that the most probable reason was the big > > number of "unused" pages. Below follows what VACUUM reported: > > > > ======================= > > vacuum verbose goods; > > NOTICE: --Relation goods-- > > NOTICE: Pages 15068: Changed 0, Empty 0; Tup 16157: Vac 0, Keep > > 0, UnUsed 465938. > > ======================= > > select count(*) from goods; > > count > > ------- > > 16157 > > > ---------------------------(end of broadcast)--------------------------- > TIP 5: Have you checked our extensive FAQ? > > http://www.postgresql.org/users-lounge/docs/faq.html Yep! Suggest to add this as well as that typical mistake with LANGUAGE/HANDLER (plpgsql.so I mean).:-) -- WBR, Yury Bokhoncovich, Senior System Administrator, NOC of F1 Group. Phone: +7 (3832) 106228, ext.140, E-mail: [EMAIL PROTECTED] Unix is like a wigwam -- no Gates, no Windows, and an Apache inside. ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/users-lounge/docs/faq.html