From: Paolo Bonzini <pbonzini@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Naredula Janardhana Reddy <naredula.jana@gmail.com>,
Fam Zheng <famz@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>,
Ming Lei <ming.lei@canonical.com>,
qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>
Subject: Re: [Qemu-devel] virtio-blk multiqueue support in qemu.
Date: Mon, 13 Jul 2015 13:24:15 +0200 [thread overview]
Message-ID: <55A39FDF.1060800@redhat.com> (raw)
In-Reply-To: <20150713141421-mutt-send-email-mst@redhat.com>
On 13/07/2015 13:21, Michael S. Tsirkin wrote:
> > Yes, this is already how virtio-scsi multiqueue is implemented. The
> > speedup is noticeable. However, for virtio-blk there is a huge
> > consumption of interrupt vectors in the guest, so it doesn't scale to
> > multiple disks as well as virtio-scsi.
>
> Could you elaborate please? interrupt vector usage is generally
> up to the guest, so whatever the issue is might be fixable by driver
> changes alone.
Yes, but in practice neither Linux nor Windows (AFAIK) are able to share
the same vector across multiple MSIs.
Paolo
next prev parent reply other threads:[~2015-07-13 11:24 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-01 17:15 [Qemu-devel] virtio-blk multiqueue support in qemu Naredula Janardhana Reddy
2015-07-02 1:21 ` Fam Zheng
2015-07-08 14:37 ` Michael S. Tsirkin
2015-07-09 9:13 ` Stefan Hajnoczi
[not found] ` <20150709132248.GA12399@stefanha-thinkpad.redhat.com>
2015-07-09 13:29 ` Michael S. Tsirkin
2015-07-10 17:56 ` Naredula Janardhana Reddy
2015-07-13 10:04 ` Stefan Hajnoczi
2015-07-13 10:17 ` Paolo Bonzini
2015-07-13 11:21 ` Michael S. Tsirkin
2015-07-13 11:24 ` Paolo Bonzini [this message]
2015-07-13 11:41 ` Michael S. Tsirkin
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