Re: PATCH: pgbench - merging transaction logs

On Sun, Mar 15, 2015 at 3:35 PM, Fabien COELHO <coelho@cri.ensmp.fr> wrote:
>> Firstly, the fact that pgbench produces one file per thread is awkward.
>
> I agree, but I think it is due to the multi process thread emulation: if you
> have real threads, you can do a simple fprintf, possibly with some mutex,
> and you're done. There is really nothing to do to implement this
> feature.

I think that's probably not a good idea, because fprintf() might then
become a bottleneck.  I fixed a similar problem with random() in
commit 4af43ee3f165c8e4b332a7e680a44f4b7ba2d3c1.  Even though the
locking was happening inside libc, it was still locking, and it still
caused a contention problem.

-- 
Robert Haas
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