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Date: Wed, 27 Dec 2023 05:06:12 -0500
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Li Feng <fengli@smartx.com>
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>
Subject: Re: [PATCH] virtio_blk: set the default scheduler to none
Message-ID: <20231227050544-mutt-send-email-mst@kernel.org>
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 <AB23804D-FF38-47B8-ADC6-C0A19B7083CC@smartx.com>
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On Wed, Dec 27, 2023 at 03:26:30PM +0800, Li Feng wrote:
> 
> 
> > On Dec 26, 2023, at 23:38, Michael S. Tsirkin <mst@redhat.com> wrote:
> > 
> > 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.
> > 
> > Paolo did some testing on this thread and posted some concerns.
> > Do you disagree with his analysis?
> 
> 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 
> caused by other problems (such as test fluctuations) rather than the benefits 
> brought by deadline. 

Maybe. I think it would be up to you to prove this then.


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