From: Tom Lane <tgl@sss.pgh.pa.us>
To: Martijn van Oosterhout <kleptog@svana.org>
Cc: Ron Peacetree <rjpeace@earthlink.net>
Cc: Jonah H. Harris <jonah.harris@gmail.com>
Cc: pgsql-hackers@postgresql.org
Cc: pgsql-performance@postgresql.org
Subject: Re: [HACKERS] A Better External Sort?
Date: Thu, 06 Oct 2005 15:57:38 -0400
Message-ID: <25130.1128628658@sss.pgh.pa.us> (raw)
In-Reply-To: <20051006165725.GF10127@svana.org>
References: <138872.1128556455518.JavaMail.root@elwamui-milano.atl.sa.earthlink.net>
<20051006165725.GF10127@svana.org>
Martijn van Oosterhout <kleptog@svana.org> writes:
> Indeed, one of the things on my list is to remove all the lseeks in
> favour of pread. Halving the number of kernel calls has got to be worth
> something right? Portability is an issue ofcourse...
Being sure that it's not a pessimization is another issue. I note that
glibc will emulate these functions if the kernel doesn't have them;
which means you could be replacing one kernel call with three.
And I don't think autoconf has any way to determine whether a libc
function represents a native kernel call or not ...
regards, tom lane
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-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, kleptog@svana.org, rjpeace@earthlink.net, jonah.harris@gmail.com, pgsql-hackers@postgresql.org
Subject: Re: [HACKERS] A Better External Sort?
In-Reply-To: <25130.1128628658@sss.pgh.pa.us>
* 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