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Message-ID: <20fb7157-05ae-eeb5-4acd-76b2c82d80b3@kernel.org>
Date:   Tue, 6 Jun 2023 14:40:34 +0800
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Subject: Re: [f2fs-dev] [PATCH] f2fs: flag as supporting buffered async reads
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To:     Jaegeuk Kim <jaegeuk@kernel.org>,
        Juhyung Park <qkrwngud825@gmail.com>
Cc:     Yangtao Li <frank.li@vivo.com>,
        linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, Lu Hongfei <luhongfei@vivo.com>
References: <20230531125918.55609-1-frank.li@vivo.com>
 <CAD14+f1YoiSVvq2M1v8u5bUdCNN_0nurY4ued6ZFu1gaBSHxDw@mail.gmail.com>
 <ZH48E4/AOtk1viOY@google.com>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <ZH48E4/AOtk1viOY@google.com>
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On 2023/6/6 3:48, Jaegeuk Kim wrote:
> On 05/31, Juhyung Park wrote:
>> Hi Yangtao,
>>
>> I remember hearing that f2fs can perform relatively poorly under io_uring,
>> nice find.
>>
>> I suggest rewriting the commit message though. From the looks of it, it
>> might suggest that FMODE_BUF_RASYNC is a magic flag that automatically
>> improves performance that can be enabled willy nilly.
>>
>> How about something like:
>>
>> f2fs uses generic_file_buffered_read(), which supports buffered async
>> reads since commit 1a0a7853b901 ("mm: support async buffered reads in
>> generic_file_buffered_read()").
> 
> Thanks Juhyung,
> 
> Applied with a minor motification based on yours. :)

The version in dev-test branch looks good to me.

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,

> 
>>
>> Match other file-systems and enable it. The read performance has been
>> greatly improved under io_uring:
>>
>>      167M/s -> 234M/s, Increase ratio by 40%
>>
>> Test w/:
>>      ./fio --name=onessd --filename=/data/test/local/io_uring_test
>>      --size=256M --rw=randread --bs=4k --direct=0 --overwrite=0
>>      --numjobs=1 --iodepth=1 --time_based=0 --runtime=10
>>      --ioengine=io_uring --registerfiles --fixedbufs
>>      --gtod_reduce=1 --group_reporting --sqthread_poll=1
>>
>> On Wed, May 31, 2023 at 10:01 PM Yangtao Li via Linux-f2fs-devel
>> <linux-f2fs-devel@lists.sourceforge.net> wrote:
>>>
>>> After enabling this feature, the read performance has been greatly
>>> improved:
>>>
>>>      167M/s -> 234M/s, Increase ratio by 40%
>>>
>>> Test w/:
>>>      ./fio --name=onessd --filename=/data/test/local/io_uring_test
>>>      --size=256M --rw=randread --bs=4k --direct=0 --overwrite=0
>>>      --numjobs=1 --iodepth=1 --time_based=0 --runtime=10
>>>      --ioengine=io_uring --registerfiles --fixedbufs
>>>      --gtod_reduce=1 --group_reporting --sqthread_poll=1
>>>
>>> Signed-off-by: Lu Hongfei <luhongfei@vivo.com>
>>> Signed-off-by: Yangtao Li <frank.li@vivo.com>
>>> ---
>>>   fs/f2fs/file.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
>>> index 015ed274dc31..23c68ee946e5 100644
>>> --- a/fs/f2fs/file.c
>>> +++ b/fs/f2fs/file.c
>>> @@ -546,7 +546,7 @@ static int f2fs_file_open(struct inode *inode, struct file *filp)
>>>          if (err)
>>>                  return err;
>>>
>>> -       filp->f_mode |= FMODE_NOWAIT;
>>> +       filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC;
>>>
>>>          return dquot_file_open(inode, filp);
>>>   }
>>> --
>>> 2.39.0
>>>
>>>
>>>
>>> _______________________________________________
>>> Linux-f2fs-devel mailing list
>>> Linux-f2fs-devel@lists.sourceforge.net
>>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel