Re: Re: Faster CREATE DATABASE by delaying fsync (was 8.4.1 ubuntu karmic slow createdb)

On Tue, 29 Dec 2009, Greg Stark wrote:

> On Mon, Dec 28, 2009 at 10:54 PM, Andres Freund <andres@anarazel.de> wrote:
>> fsync everything in that pass.
>> Including the directory - which was not done before and actually might be
>> necessary in some cases.
>
> Er. Yes. At least on ext4 this is pretty important. I wish it weren't,
> but it doesn't look like we're going to convince the ext4 developers
> they're crazy any day soon and it would really suck for a database
> created from a template to have files in it go missin.

actually, as I understand it you need to do this on all filesystems except 
ext3, and on ext3 fsync is horribly slow because it writes out 
_everything_ that's pending, not just stuff related to the file you do the 
fsync on.

David Lang