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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Mon, 24 Sep 2018 17:04:13 +0200
Message-ID: <CAJfpegt60Bcmu+fHRTL-HE-Uw5rvP3Nb_yuzfpX02E9Z8ECbdg@mail.gmail.com>
Subject: Re: [PATCH 0/3] fuse: Solve request_find() bottleneck
To:     Kirill Tkhai <ktkhai@virtuozzo.com>
Cc:     kuznet@virtuozzo.com, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Mon, Sep 24, 2018 at 2:08 PM, Kirill Tkhai <ktkhai@virtuozzo.com> wrote:
> 2 weeks passed, so ping.
>
> Miklos, any reaction on this?
>
> Thanks,
> Kirill
>
> On 11.09.2018 13:11, Kirill Tkhai wrote:
>> Hi,
>>
>> We noticed the performance bottle neck in FUSE running our
>> Virtuozzo storage over rdma. On some types of workload
>> we observe 20% of time spent in request_find() in profiler.
>> This function is iterating over long list of requests, and it
>> scales bad.
>>
>> The patch introduces hash table to reduce the number
>> of iterations, we do in this function. Also, algorithm
>> of generating IDs for interrupt requests is changed,
>> simplified request_find() function and killed
>> fuse_req::intr_unique field.

Concept looks good.  Will review details...

Thanks,
Miklos