From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 7 Mar 2001 11:16:19 +0000 (GMT) From: Matthew Kirkwood Subject: Re: Linux 2.2 vs 2.4 for PostgreSQL In-Reply-To: <20010307102206.C7453@redhat.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: "Stephen C. Tweedie" Cc: linux-mm@kvack.org, Mike Galbraith , Rik van Riel List-ID: On Wed, 7 Mar 2001, Stephen C. Tweedie wrote: > > 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/