Re: fallocate / posix_fallocate for new WAL file creation (etc...)

On 6/14/13 1:06 PM, Jeff Davis wrote:
> Why have a GUC here at all? Perhaps this was already discussed, and I
> missed it? Is it just for testing purposes, or did you intend for it to
> be in the final version?

You have guessed correctly! I suggested it stay in there only to make
review benchmarking easier.

> I started looking at this patch and it looks like we are getting a
> consensus that it's the right approach. Microbenchmarks appear to show a
> benefit, and (thanks to Noah's comment) it seems like the change is
> safe. Are there any remaining questions or objections?

I'm planning to duplicate Jon's test program on a few machines here, and
then see if that turns into a useful latency improvement for clients.
I'm trying to get this pgbench rate limit stuff working first though,
because one of the tests I had in mind for WAL creation overhead would
benefit from it.

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
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