Re: Proposed LogWriter Scheme, WAS: Potential Large
Hannu Krosing <hannu@tm.ee>
From: Hannu Krosing <hannu@tm.ee>
To: Neil Conway <neilc@samurai.com>
Cc: Greg Copeland <greg@CopelandConsulting.Net>, Antti Haapala <antti.haapala@iki.fi>, Curtis Faith <curtis@galtair.com>, Bruce Momjian <pgman@candle.pha.pa.us>, Pgsql-Hackers <pgsql-hackers@postgresql.org>
Date: 2002-10-07T19:32:42Z
Lists: pgsql-hackers
On Mon, 2002-10-07 at 21:35, Neil Conway wrote: > Greg Copeland <greg@CopelandConsulting.Net> writes: > > Ya, I have read this before. The problem here is that I'm not aware of > > which AIO implementation on Linux is the forerunner nor do I have any > > idea how it's implementation or performance details defer from that of > > other implementations on other platforms. > > The implementation of AIO in 2.5 is the one by Ben LaHaise (not > SGI). Not sure what the performance is like -- although it's been > merged into 2.5 already, so someone can do some benchmarking. Can > anyone suggest a good test? What would be really interesting is to aio_write small chunks to the same 8k page by multiple threads/processes and then wait for the page getting written to disk. Then check how many backends get their wait back at the same write. The docs for POSIX aio_xxx are at: http://www.opengroup.org/onlinepubs/007904975/functions/aio_write.html ---------------- Hannu