Re: SCSI vs. IDE performance test - Mailing list pgsql-general

From Rick Gigger
Subject Re: SCSI vs. IDE performance test
Date
Msg-id 004e01c39d9d$9a16aef0$0700a8c0@trogdor
Whole thread Raw
In response to Re: SCSI vs. IDE performance test  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-general
> "Rick Gigger" <rick@alpinenetworking.com> writes:
> >> "we have no portable means of expressing that exact constraint to the
> >> kernel"
> > Does this mean that specific operating systems have a better way of
dealing
> > with this?  Which ones and how?
>
> I'm not aware of any that offer a way of expressing "write these
> particular blocks before those particular blocks".  It doesn't seem like
> it would require rocket scientists to devise such an API, but no one's
> got round to it yet.  Part of the problem is that the issue would have
> to be approached at multiple levels: there is no point in offering an
> OS-level API for this when the hardware underlying the bus-level API
> (IDE) is doing its level best to sabotage the entire semantics.

But for those of us using scsi wouldn't it be possible to get a performance
gain here?  Would the gain be worth the effort?


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