Re: Write ahead logging - Mailing list pgsql-performance

From Rod Taylor
Subject Re: Write ahead logging
Date
Msg-id 1046993755.487.86.camel@jester
Whole thread Raw
In response to Re: Write ahead logging  (Matthias Meixner <meixner@dvs1.informatik.tu-darmstadt.de>)
Responses Re: Write ahead logging
List pgsql-performance
What were you using to measure the latency.  Don't suppose you could
send it over.  The admins locally don't like what I used to do the test
with -- they don't want to turn off write-caching for other reasons.

On Fri, 2003-02-21 at 03:52, Matthias Meixner wrote:
> Mario Weilguni wrote:
> >>>So the question is: has anybody verified, that the log is written to disk
> >>>before returning from commit?
> >>
> >>Some (or all?) IDE disks are known to lie:  they report success as
> >>soon as the data have reached the drive's RAM.
> >
> >
> > under linux, hdparm -W can turn off the write cache of IDE disk, maybe you
> > should try with write-caching turned off.
>
> Yes, that made a big difference. Latency went up to 25-95ms.
>
> Regards,
>
>     Matthias Meixner
--
Rod Taylor <rbt@rbt.ca>

PGP Key: http://www.rbt.ca/rbtpub.asc

Attachment

pgsql-performance by date:

Previous
From: Neil Conway
Date:
Subject: Re: OIDs as keys
Next
From: Sean Chittenden
Date:
Subject: Re: [COMMITTERS] pgsql-server/ /configure /configure.in rc/incl ...