Messages in this thread | | | Date | Wed, 14 Jan 2015 18:17:24 +0800 | Subject | Re: [PATCH v2 0/4] block & aio: improve loop with kernel aio | From | Ming Lei <> |
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On Wed, Jan 14, 2015 at 12:23 AM, Christoph Hellwig <hch@infradead.org> wrote: > On Tue, Jan 13, 2015 at 11:44:44PM +0800, Ming Lei wrote: >> Follows benefits from using kernel aio in loop: >> - avoid double cache, and memory usage decreased a lot >> - system load gets much decreased > > This seems to conflate two changes: > > 1) use direct I/O > 2) use aio (require 1) > > what numbers do you get when just using direct I/O?
I don't run the direct I/O only test because it needs quite changes on current patches, such as: make the kiocb as sync, allow all dio requests running concurrently for sake of throughput.
IMO, without aio, context switches will be increased inevitably, and CPU will be wasted, so could you explain if there is advantage of not using aio?
Thanks, Ming Lei
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