Re: Raw devices vs. Filesystems

> gsw(at)globexplorer(dot)com ("Gregory S. Williamson") writes:
>>No point to beating a dead horse (other than the sheer joy of the
>>thing) since postgres does not have raw device support, but ... raw
>>devices, at least on solaris, are about 10 times as fast as cooked
>>file systems for Informix. This might still be a gain for postgres'
>>performance, but the portability issues remain.

> From: Chris Browne [mailto:cbbrowne(at)acm(dot)org]
> That claim seems really rather remarkable.
> It implies an entirely stunning degree of inefficiency in the
> implementation of filesystems on Solaris.
> The amount of indirection involved in walking through i-nodes and such
> is something I would expect to introduce some percentage of
> performance loss, but for it to introduce overhead of over 900%
> presumably implies that Sun (and/or Veritas) got something really
> horribly wrong.

Gregory S. Williamson wrote:
> Remarkable, perhaps, to you. Not in the Informix world. But
> irrelevant to postgres, no ?

I too am a little surprised by those numbers, but I think the potential
for a performance gain of that order is relevant.

As I once heard someone remark: "When show up at a pool hall talking
those kind of odds, well, people start making phone calls."

- Marsh