From: Tom Lane <tgl@sss.pgh.pa.us>
To: Craig Ringer <craig@postnewspapers.com.au>
Cc: David Newall <postgresql@davidnewall.com>
Cc: pgsql-performance@postgresql.org
Cc: robertmhaas@gmail.com
Cc: dcrooke@gmail.com
Subject: Re: pg_dump far too slow
Date: Sun, 21 Mar 2010 11:39:04 -0400
Message-ID: <22117.1269185944@sss.pgh.pa.us> (raw)
In-Reply-To: <4BA62596.8050604@postnewspapers.com.au>
References: <4B9C97E1.40509@davidnewall.com>
<24696.1268598111@sss.pgh.pa.us>
<4BA61C74.70506@davidnewall.com>
<4BA62596.8050604@postnewspapers.com.au>
Craig Ringer <craig@postnewspapers.com.au> writes:
> On 21/03/2010 9:17 PM, David Newall wrote:
>> and wonder if I should read up on gzip to find why it would work so
>> slowly on a pure text stream, albeit a representation of PDF which
>> intrinsically is fairly compressed.
> In fact, PDF uses deflate compression, the same algorithm used for gzip.
> Gzip-compressing PDF is almost completely pointless -
Yeah. I would bet that the reason for the slow throughput is that gzip
is fruitlessly searching for compressible sequences. It won't find many.
regards, tom lane
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Subject: Re: pg_dump far too slow
In-Reply-To: <22117.1269185944@sss.pgh.pa.us>
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