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Date: Tue, 10 Nov 2009 12:55:42 +0100
Message-ID: <8a1bfe660911100355l34a557ffj8244079c1fb689b5@mail.gmail.com>
Subject: limiting performance impact of wal archiving.
From: Laurent Laborde <kerdezixe@gmail.com>
To: PostgreSQL Performance <pgsql-performance@postgresql.org>
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Hi !
We recently had a problem with wal archiving badly impacting the
performance of our postgresql master.
And i discovered "cstream", that can limite the bandwidth of pipe stream.

Here is our new archive command, FYI, that limit the IO bandwidth to 500KB/s  :
archive_command = '/bin/cat %p | cstream -i "" -o "" -t -500k | nice
gzip -9 -c | /usr/bin/ncftpput etc...'


PS : While writing that mail, i just found that i could replace :
cat %p | cstream -i "" ...
with
cstream -i %p ...
*grins*


-- 
ker2x
Sysadmin & DBA @ http://Www.over-blog.com/