Re: Bumping block size to 16K on FreeBSD...

Marc G. Fournier wrote:
> Now, here's a question for someone running a non-FreeBSD OS ... if we were
> to jump the BLCKSZ to 16k, would it cause a degradation in performance, or
> would it make no difference to them? Would they see an 8% reduction in
> performance?
>
> The thing is ... there has been presented a strong, valid reason for
> moving to 16k (at least under FreeBSD) ... and there has been a valid
> reason for not making it "easily configurable" ... but, are there any
> strong reasons not to just move to 16k across the board?

First, I assume all this discussion about default block size is for 7.5,
not for 7.4, which is in beta. Second, the tests were done only for
_write_ performance. We can expect random read performance to be worse
for larger block sizes, so I think more research needs to be done.
Also, Tatsuo reported years ago that he got ~15% performance improvement
with a 32k PostgreSQL block size. The OS was AIX or Linux.

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