Re: [PERFORM] fsync method checking

Josh Berkus wrote:
> Tom, Bruce,
>
> > My previous point about checking different fsync spacings corresponds to
> > different assumptions about average transaction size.  I think a useful
> > tool for determining wal_sync_method has got to be able to reflect that
> > range of possibilities.
>
> Questions:
> 1) This is an OSS project.   Why not just recruit a bunch of people on
> PERFORMANCE and GENERAL to test the 4 different synch methods using real
> databases?   No test like reality, I say ....

Well, I wrote the program to allow testing.  I don't see a complex test
as being that much better than simple one.  We don't need accurate
numbers.  We just need to know if fsync or O_SYNC is faster.

>
> 2) Won't Jan's work on 7.5 memory and I/O management mean that we have to
> re-evaluate synching anyway?

No, it should not change sync issues.

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