Re: Higher than expected disk write(2) latency

[Alan Cox]

> What we see is that AIO performs rather bad while we are still 
> enqueueing more writes (it misses right position on the disk and has to 
> do superfluous disk revolvings), however, once we stop enqueueing new 
> write request, those already in the queue are processed swiftly.

Which disk scheduler are you using - some of the disk schedulers
intentionally delay writes to try and get better block merging.

Alan
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