Date: Thu, 15 Nov 2007 11:05:44 -0500
From: Jean-David Beyer <jeandavid8@verizon.net>
Subject: Is there anything special about pg_dump's compression?
To: pgsql-sql@postgresql.org
Message-id: <473C6E58.5010102@verizon.net>
Organization: Institute for Regimented Whimsey
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When I run pg_dump, the computer spends a great amount of time in "system"
state. Like 100% of one cpu and part of another. The small part seems to be
the postgreSQL server, and the big part the client (pg_dump) compressing the
data.

Now my tape drive has built-in compression anyway (although I could turn it
off). I prefer to let the hardware compression run since it is a nuisance to
turn it on and off and I want it on for my normal backups of the rest of the
system.

Does pg_dump's compression do anything really special that it is not likely
the tape drive already does? The drive claims 2:1 compression for average
data (e.g., not already compressed stuff like .jpeg files).


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