Re: Assert Levels - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Assert Levels
Date
Msg-id 13370.1222036956@sss.pgh.pa.us
Whole thread Raw
In response to Assert Levels  (Simon Riggs <simon@2ndQuadrant.com>)
List pgsql-hackers
Greg Smith <gsmith@gregsmith.com> writes:
> The next time I'm doing some performance testing I'll try to quantify how 
> much damage the expensive ones do by playing with pg_config_manual.h. 
> Normally I'm testing with 1GB+ of shared_buffers which makes the current 
> assert scheme unusable.

There is a commit-time scan of the buffers for the sole purpose of
asserting a few things about their state.  That's one of the things
we'd need to turn off for a "cheap asserts only" mode I think.

If you want to try to quantify what "cheap asserts" might do, you
should pull out the #ifdef USE_ASSERT_CHECKING code here:check_list_invariants in list.cthe loops in AtEOXact_Buffers
andAtEOXact_LocalBuffersthe loop in AtEOXact_CatCachethe test that makes AtEOXact_RelationCache scan the relcache
evenwhen !need_eoxact_work
 
in addition to the memory-related stuff.
        regards, tom lane


pgsql-hackers by date:

Previous
From: Andrew Dunstan
Date:
Subject: parallel pg_restore
Next
From: "Marko Kreen"
Date:
Subject: Re: [patch] fix dblink security hole