Re: Increasing system speed by using -F option

Mitch Vincent wrote:
>
> -F makes PG *not* call fsync(), therefore the risk of corruption and the
> speed increase. (The good, the bad and if it crashes , the ugly)
>
> It's possible to speed up queries by increasing your -B and -S parameters to
> use some more memory.. There is also a lot to be said for _proper_ use of
> indexes ( Use EXPLAIN!)..
>
> If you could give us a little more information about the tables you're
> searching and the queries you're using, maybe we could provide some more
> specific help..
>
> Good luck!
>
> ----- Original Message -----
> From: "Mark Alliban" <MarkA(at)idnltd(dot)com>
> To: <pgsql-general(at)postgresql(dot)org>
> Sent: Friday, September 01, 2000 5:53 AM
> Subject: [GENERAL] Increasing system speed by using -F option
>
> Hi,
>
> I notice a dramatic speed increase (3 to 4 times faster) by using the -F
> option when starting the database, at a cost of database corruption if the
> OS crashes. This database is mission-critical so data reliability is
> extremely important, meaning I cannot use the -F option. Are there any ways
> of achieving similar speed increases without using the -F option? I am using
> RedHat 6.1, 7.0.2, -B 2048 -N 1024 -i.
>
> Thanks,
> Mark.

Well from my experience the reason systems crash are hardware failuers
or power failuers. If your hard disk crashes it won't make any differnce
whether you fsync was on off, you are reloading from backups unless you
are running araid system. If the system is a mission critical one then
I'd assume you would have some sort of UPS or alternate power supply..
it would seem that the chances of a hardware failure is minimal leaving
the fsync off is probably pretty safe.

--
Dave Smith
Candata Systems Ltd.
(416) 493-9020
dave(at)candata(dot)com