Tobias Oberstein wrote:
> I am benchmarking IOPS, and while doing so, it becomes apparent that at
> these scales it does matter _how_ IO is done.
>
> The most efficient way is libaio. I get 9.7 million/sec IOPS with low CPU
> load. Using any synchronous IO engine is slower and produces higher load.
>
> I do understand that switching to libaio isn't going to fly for PG
> (completely different approach).
Maybe it is possible to write a new f_smgr implementation (parallel to
md.c) that uses libaio. There is no "seek" in that interface, at least,
though the interface does assume that the implementation is blocking.
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Álvaro Herrera https://www.2ndQuadrant.com/
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