Re: Changing the default wal_sync_method to open_sync for Win32?

> -----Original Message-----
> From: pgsql-hackers-owner(at)postgresql(dot)org
> [mailto:pgsql-hackers-owner(at)postgresql(dot)org] On Behalf Of Bruce Momjian
> Sent: 17 March 2005 04:20
> To: Magnus Hagander
> Cc: Tom Lane; pgsql-hackers(at)postgresql(dot)org;
> pgsql-hackers-win32(at)postgresql(dot)org; Merlin Moncure
> Subject: [HACKERS] Changing the default wal_sync_method to
> open_sync for Win32?
>
> 1. Should it be the default wal_sync_method for Win32?

Yes.

> 2. Another question is what to do with 8.0.X? Do we
> backpatch this for
> Win32 performance? Can we test it enough to know it will work well?
> 8.0.2 is going to have a more rigorous testing cycle because of the
> buffer manager changes.

This question was asked earlier, and iirc, a few people said yes, and
no-one said no. I'm most definitely in the yes camp.

Regards, Dave.

Dave Page wrote:
> > 2. Another question is what to do with 8.0.X? Do we
> > backpatch this for
> > Win32 performance? Can we test it enough to know it will work well?
> > 8.0.2 is going to have a more rigorous testing cycle because of the
> > buffer manager changes.
>
> This question was asked earlier, and iirc, a few people said yes, and
> no-one said no. I'm most definitely in the yes camp.

I have backpatched O_SYNC for Win32 to 8.0.X. Everyone seems to agree
it should be supported by wal_sync_method. --- the "default" issue
still needs discussion.

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

On Thu, 17 Mar 2005, Bruce Momjian wrote:

> Dave Page wrote:
>>> 2. Another question is what to do with 8.0.X? Do we
>>> backpatch this for
>>> Win32 performance? Can we test it enough to know it will work well?
>>> 8.0.2 is going to have a more rigorous testing cycle because of the
>>> buffer manager changes.
>>
>> This question was asked earlier, and iirc, a few people said yes, and
>> no-one said no. I'm most definitely in the yes camp.
>
> I have backpatched O_SYNC for Win32 to 8.0.X. Everyone seems to agree
> it should be supported by wal_sync_method. --- the "default" issue
> still needs discussion.

Even with Magnus' explanation that we're talking Hardware, and not OS risk
issues, I still think that the default should be the "least risky", with
the other options being well explained from both a risk/performance
standpoint, so that its a conscious decision on the admin's side ...

Any 'risk of data loss' has always been taboo, making the default
behaviour be to increase that risk seems to be a step backwards to me ..
having the option, fine ... effectively forcing that option is what I'm
against (and, by forcing, I mean how many ppl "change from the default"?)

----
Marc G. Fournier Hub.Org Networking Services (http://www.hub.org)
Email: scrappy(at)hub(dot)org Yahoo!: yscrappy ICQ: 7615664

Marc G. Fournier wrote:
> On Thu, 17 Mar 2005, Bruce Momjian wrote:
>
> > Dave Page wrote:
> >>> 2. Another question is what to do with 8.0.X? Do we
> >>> backpatch this for
> >>> Win32 performance? Can we test it enough to know it will work well?
> >>> 8.0.2 is going to have a more rigorous testing cycle because of the
> >>> buffer manager changes.
> >>
> >> This question was asked earlier, and iirc, a few people said yes, and
> >> no-one said no. I'm most definitely in the yes camp.
> >
> > I have backpatched O_SYNC for Win32 to 8.0.X. Everyone seems to agree
> > it should be supported by wal_sync_method. --- the "default" issue
> > still needs discussion.
>
> Even with Magnus' explanation that we're talking Hardware, and not OS risk
> issues, I still think that the default should be the "least risky", with
> the other options being well explained from both a risk/performance
> standpoint, so that its a conscious decision on the admin's side ...
>
> Any 'risk of data loss' has always been taboo, making the default
> behaviour be to increase that risk seems to be a step backwards to me ..
> having the option, fine ... effectively forcing that option is what I'm
> against (and, by forcing, I mean how many ppl "change from the default"?)

I understand that logic. Please see my posting that their fsync is
something we don't have on Unix.

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

> Even with Magnus' explanation that we're talking Hardware, and not OS
> risk issues, I still think that the default should be the "least risky",
> with the other options being well explained from both a risk/performance
> standpoint, so that its a conscious decision on the admin's side ...
>
> Any 'risk of data loss' has always been taboo, making the default
> behaviour be to increase that risk seems to be a step backwards to me ..
> having the option, fine ... effectively forcing that option is what I'm
> against (and, by forcing, I mean how many ppl "change from the default"?)

But doesn't making it the default just make it identical to the default
freebsd configuration? ie. Identical risk?

Chris