Re: Impact of checkpoint_segments under continual load conditions - Mailing list pgsql-performance

From Christopher Petrilli
Subject Re: Impact of checkpoint_segments under continual load conditions
Date
Msg-id 59d991c4050719122213ac3d81@mail.gmail.com
Whole thread Raw
In response to Re: Impact of checkpoint_segments under continual load conditions  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Impact of checkpoint_segments under continual load conditions
List pgsql-performance
On 7/19/05, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Christopher Petrilli <petrilli@gmail.com> writes:
> > On 7/19/05, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> How *exactly* are you invoking psql?
>
> > It is a subprocess of a Python process, driven using a pexpect
> > interchange. I send the COPY command, then wait for the '=#' to come
> > back.
>
> Some weird interaction with pexpect maybe?  Try adding "-n" (disable
> readline) to the psql command switches.

Um... WOW!

==> pgsql_benchmark_803_bigbuffers10000_noreadline.txt <==
0       0.0319459438324 0.0263829231262
1       0.0303978919983 0.0263390541077
2       0.0306499004364 0.0273139476776
3       0.0306959152222 0.0270659923553
4       0.0307791233063 0.0278429985046
5       0.0306351184845 0.0278820991516
6       0.0307800769806 0.0335869789124
7       0.0408310890198 0.0370559692383
8       0.0371310710907 0.0344209671021
9       0.0372560024261 0.0334041118622

==> pgsql_benchmark_803_bigbuffers10000.txt <==
0       0.0352520942688 0.149132013321
1       0.0320160388947 0.146126031876
2       0.0307128429413 0.139330863953
3       0.0306718349457 0.139590978622
4       0.0307030677795 0.140225172043
5       0.0306420326233 0.140012979507
6       0.0307261943817 0.139672994614
7       0.0307750701904 0.140661001205
8       0.0307800769806 0.141661167145
9       0.0306720733643 0.141198158264

First column is iteration, second is "gen time" to generate the load
file, and 3rd is "load time".

It doesn't stay QUITE that low, but it stays lower... quite a bit.
We'll see what happens over time.

Chris
--
| Christopher Petrilli
| petrilli@gmail.com

pgsql-performance by date:

Previous
From: Tom Lane
Date:
Subject: Re: Looking for tips
Next
From: Robert Creager
Date:
Subject: Re: Huge performance problem between 7.4.1 and 8.0.3 - CS issue?