Re: Write ahead logging

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>

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