Skip site navigation (1) Skip section navigation (2)

Re: Random plan selection in DBT-3

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: ITAGAKI Takahiro <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Random plan selection in DBT-3
Date: 2008-01-07 03:26:42
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-hackers
ITAGAKI Takahiro <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp> writes:
> There might be regularity in the plan selection. When I connect to postgres
> newly, I see plans { A, B, A, A ... }. Then disconnect, re-connect and send
> the same EXPLAINs, the same pattern was reproduced.

Hmph ... maybe some effect associated with loading up the backend's
internal caches?  I can't imagine what though.

Please see if you can extract a more self-contained test case.

			regards, tom lane

In response to

pgsql-hackers by date

Next:From: Joshua D. DrakeDate: 2008-01-07 05:59:54
Subject: Re: Bug: Unreferenced temp tables disables vacuum to update xid
Previous:From: ITAGAKI TakahiroDate: 2008-01-07 03:06:49
Subject: Re: Random plan selection in DBT-3

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group