From: Himanshu Baweja <himanshubaweja@yahoo.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Moving pg_xlog
Date: Thu, 2 Jun 2005 07:47:21 -0700 (PDT)
Message-ID: <20050602144721.15002.qmail@web51004.mail.yahoo.com> (raw)
In-Reply-To: <13548.1117722203@sss.pgh.pa.us>
Tom Lane <tgl@sss.pgh.pa.us> wrote:
>It seems highly unlikely that putting more stuff on the xlog disk will
>improve performance --- at least not if your bottleneck is update speed.
Tom you are right.. i did some testing...
1) default config--- xlog on disk1 and data on disk2=>
27 mins and 22 secs
2) xlog and some tables on disk1 and rest of tables on disk2=>
28 mins and 38 secs
but the most startling of the results is....
3) xlog on disk1 and half the tables on partition 1 of disk2 and other half on partition 2 of disk2
24 mins and 14 secs
??????????
shouldnt moving data to diff partitions degrade performance instead of enhancing it....
also in configuration 1, my heap_blks_hit/heap_blks_fetched was good enough....
but in configuration 3, its was really low.. something of the order of 1/15...
still the performance improved....
any ideas.....
does moving across partitions help...
Regards
Himanshu
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To: pgsql-performance@postgresql.org
Cc: himanshubaweja@yahoo.com, tgl@sss.pgh.pa.us
Subject: Re: Moving pg_xlog
In-Reply-To: <20050602144721.15002.qmail@web51004.mail.yahoo.com>
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