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Subject: Re: [PATCH] virtio_blk: set the default scheduler to none
From: Li Feng <fengli@smartx.com>
In-Reply-To: <20231227050544-mutt-send-email-mst@kernel.org>
Date: Thu, 28 Dec 2023 15:25:10 +0800
Cc: Paolo Bonzini <pbonzini@redhat.com>,
 Jens Axboe <axboe@kernel.dk>,
 Jason Wang <jasowang@redhat.com>,
 Stefan Hajnoczi <stefanha@redhat.com>,
 Xuan Zhuo <xuanzhuo@linux.alibaba.com>,
 "open list:BLOCK LAYER" <linux-block@vger.kernel.org>,
 linux-kernel <linux-kernel@vger.kernel.org>,
 "open list:VIRTIO BLOCK AND SCSI DRIVERS" <virtualization@lists.linux.dev>
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To: "Michael S. Tsirkin" <mst@redhat.com>


> On Dec 27, 2023, at 18:06, Michael S. Tsirkin <mst@redhat.com> wrote:
>=20
> On Wed, Dec 27, 2023 at 03:26:30PM +0800, Li Feng wrote:
>>=20
>>=20
>>> On Dec 26, 2023, at 23:38, Michael S. Tsirkin <mst@redhat.com> =
wrote:
>>>=20
>>> On Tue, Dec 26, 2023 at 05:01:40PM +0800, Li Feng wrote:
>>>> I don't have ideas right now to answer Christoph/Paolo's question.
>>>=20
>>> Paolo did some testing on this thread and posted some concerns.
>>> Do you disagree with his analysis?
>>=20
>> Paolo gave a very detailed data analysis. Indeed, in some low queue =
depth
>> scenarios, the data dropped somewhat. However, I suspect that it may =
be=20
>> caused by other problems (such as test fluctuations) rather than the =
benefits=20
>> brought by deadline.
>=20
> Maybe. I think it would be up to you to prove this then.
Ok.

>=20
>=20
>> BTW, I think 128 queue depth test is a very important and common =
performance
>> test item for storage devices.
>>=20
>> Thanks,
>> Li
>>=20
>>>=20
>>> --=20
>>> MST
>>>=20
>=20