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From: "Wangting (Kathy)" <kathy.wangting@huawei.com>
To: pbonzini@redhat.com
Cc: qemu-devel <qemu-devel@nongnu.org>
Subject: [Qemu-devel] [question] the patch which affect performance of virtio-scsi
Date: Tue, 3 Feb 2015 10:31:23 +0800	[thread overview]
Message-ID: <54D032FB.404@huawei.com> (raw)

Hi Paolo,

Recently I test IO performance with virtio-scsi, and find out that the patch of
"virtio-scsi: add support for the any_layout feature" affects IO performance of model
with 4KB 32iodepth sequence read.

Why cdb and sense is removed from the struct of VirtIOSCSICmdReq and VirtIOSCSICmdResp?
How do you consider the impact of the changes to the performance?
Although the latest version of qemu can optimize the performance by the way of reading merger,
I think the affect of this patch cannot be ignored.

Best wishes,

Ting

             reply	other threads:[~2015-02-03  2:31 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-03  2:31 Wangting (Kathy) [this message]
2015-02-03  2:56 ` [Qemu-devel] [question] the patch which affect performance of virtio-scsi Wangting (Kathy)
2015-02-03  8:49   ` Paolo Bonzini
2015-02-07 11:26     ` Wangting (Kathy)
2015-02-08 10:10       ` Paolo Bonzini
2015-02-09  2:53         ` Wangting (Kathy)
2015-02-03  8:42 ` Paolo Bonzini

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