Re: Linux 2.2 vs 2.4 for PostgreSQL
From: Matthew Kirkwood <hidden>
Date: 2001-03-07 11:16:19
On Wed, 7 Mar 2001, Stephen C. Tweedie wrote:
quoted
Postgres is fairly fsync-happy.Do you happen to know if it is using fsync, fdatasync or O_SYNC? I'm seeing performance regressions on 2.4 fsync versus 2.2 which I'm chasing right now, but fdatasync doesn't seem to have that problem (and fdatasync is always preferable if you are updating a file in place and you don't care about the mtime timestamp being 100% uptodate).
The version I did these numbers on uses fsync(), but they have recently changed that to fdatasync() in a few applicable places. I don't have that installed on my test machine yet, but will have a look if it's deemed intersting. Matthew. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/