Re: [PATCHES] O_DIRECT for WAL writes

Tom Lane wrote:
> Gavin Sherry <swm(at)linuxworld(dot)com(dot)au> writes:
> >> Curt Sampson <cjs(at)cynic(dot)net> writes:
> >>> But is it really a problem? I somewhere got the impression that some
> >>> drives, on power failure, will be able to keep going for long enough to
> >>> write out the cache and park the heads anyway. If so, the drive is still
> >>> guaranteeing the write.
>
> > I've seen discussion about disks behaving this way. There's no magic:
> > they're battery backed.
>
> Oh, sure, then it's easy ;-)
>
> The bottom line here seems to be the same as always: you can't run an
> industrial strength database on piece-of-junk consumer grade hardware.
> Our problem is that because the software is free, people expect to run
> it on bottom-of-the-line Joe Bob's Bait And PC Shack hardware, and then
> they blame us when they don't get the same results as the guy running
> Oracle on million-dollar triply-redundant server hardware. Oh well.

At least we have an FAQ on this:

<H3><A name="3.7">3.7</A>) What computer hardware should I use?</H3>

<P>Because PC hardware is mostly compatible, people tend to believe that
all PC hardware is of equal quality. It is not. ECC RAM, SCSI, and
quality motherboards are more reliable and have better performance than
less expensive hardware. PostgreSQL will run on almost any hardware,
but if reliability and performance are important it is wise to
research your hardware options thoroughly. Our email lists can be used
to discuss hardware options and tradeoffs.</P>

--
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