Re: [PATCH] FUSE: Improve aio directIO write performance for size extending writes.

[Miklos Szeredi]

On Thu, Jun 16, 2016 at 1:51 PM, Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
> On Thu, Jun 16, 2016 at 1:25 PM, Miklos Szeredi <miklos@xxxxxxxxxx> wrote:
>> On Thu, Apr 7, 2016 at 1:48 PM, Ashish Sangwan <ashishsangwan2@xxxxxxxxx> wrote:
>>> While sending the blocking directIO in fuse, the write request is broken
>>> into sub-requests, each of default size 128k and all the requests are sent
>>> in non-blocking background mode if async_dio mode is supported by libfuse.
>>> The process which issue the write wait for the completion of all the
>>> sub-requests. Sending multiple requests parallely gives a chance to perform
>>> parallel writes in the user space fuse implementation if it is
>>> multi-threaded and hence improves the performance.
>>>
>>> When there is a size extending aio dio write, we switch to
>>> blocking mode so that we can properly update the size of the file after
>>> completion of the writes. However, in this situation all the sub-requests
>>> are sent in serialized manner where the next request is sent only after
>>> receiving the reply of the current request. Hence the multi-threaded user
>>> space implementation is not utilized properly.
>>>
>>> This patch changes the size extending aio dio behavior to exactly follow
>>> blocking dio. For multi threaded fuse implementation having 10 threads and
>>> using buffer size of 64MB to perform async directIO, we are getting double
>>> the speed.
>>>
>>> Signed-off-by: Ashish Sangwan <ashishsangwan2@xxxxxxxxx>
>>
>> Thanks for you patience.  Pushed to
>>
>>   git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next
>>
>> I simplified the logic, please verify that I didn't mess something up.
>>
>
> Hi,
>
> I would like to test fuse-next on Ubuntu/precise aka 12.04-LTS AMD64.
>
> Do I need a modern version of libfuse?
> Libfuse v2.8.6 is installed here.

Fuse will work fine but AFAICS the "async_dio" option was not added to
a 2.X release (it could be backported quite simply if needed).

Thanks,
Miklos