From: Jan Lentfer <Jan.Lentfer@web.de>
To: pgsql-admin@postgresql.org
Subject: Re: pg_dump and pg_restore with multiple streams does Not seem to improve overall times
Date: Mon, 04 May 2015 14:14:01 +0200
Message-ID: <d2d0b6691081e6e714f61d9d9db39a13@imap.lan.net> (raw)
In-Reply-To: <CAOR=d=1OJQfkmygTDL_eVWMAEkFJbsvWb3=+QSf+g5Ct8T1ToQ@mail.gmail.com>
References: <em5e30e63a-661c-44ad-8996-601c945efc8b@oyster-creek>
<CAOR=d=1OJQfkmygTDL_eVWMAEkFJbsvWb3=+QSf+g5Ct8T1ToQ@mail.gmail.com>
List-Unsubscribe: <mailto:majordomo@postgresql.org?body=unsub%20pgsql-admin>
Am 2015-05-01 17:49, schrieb Scott Marlowe:
> On Fri, May 1, 2015 at 9:16 AM, Susan K. McClure <smcclure@rice.edu
> [1]> wrote:
>
>> Running postgresql 9-4 on REHL 7 system. I am trying to speed up
>> pg_dump and pg_restore by
>> using a postgresql.conf with various performance options set, and
>> the --jobs option to force multiple
>> streams. But various tests, with various "--jobs=" numbers only
>> achieve at most a 1 minute improvement
>> in elapsed time versus doing pg_dump or pg_restore with no "--jobs"
>> option and no postgresql.conf with performance
>> options. Am I missing some key option(s) to improve things??
>>
>> The DB in question is ~25GB. The processor has 24 Cpus, 12 cores
>>
>> I have tried with "--jobs = 8, 12, and 20" with little or no
>> discernible improvements.
>
> So have you tried 2 jobs first? Id see how 1, 2, 3, 4 etc work. See
> if
> 2 is faster than 1, then 3 faster than 2 etc.
>
> Most of the time, unless youve got a really fast IO subsystem
> increasing the --jobs doesnt make a big difference as a lot of the
> work is sequential. Also on restores I think the extra jobs part only
> kicks in for index builds.
It does parallel COPY, too.
Jan
--
Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-admin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: Jan.Lentfer@web.de
Subject: Re: pg_dump and pg_restore with multiple streams does Not seem to improve overall times
In-Reply-To: <d2d0b6691081e6e714f61d9d9db39a13@imap.lan.net>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox