Re: [RFC PATCH 0/9] vhost-nvme: new qemu nvme backend using nvme target
From: Ming Lin <mlin@kernel.org>
Date: 2015-12-01 16:26:11
Also in:
linux-nvme, qemu-devel
Possibly related (same subject, not in this thread)
- 2015-11-21 · Re: [RFC PATCH 0/9] vhost-nvme: new qemu nvme backend using nvme target · Paolo Bonzini <pbonzini@redhat.com>
- 2015-11-20 · [RFC PATCH 0/9] vhost-nvme: new qemu nvme backend using nvme target · mlin@kernel.org (Ming Lin)
- 2015-11-20 · Re: [RFC PATCH 0/9] vhost-nvme: new qemu nvme backend using nvme target · Christoph Hellwig <hch@lst.de>
- 2015-11-20 · [RFC PATCH 0/9] vhost-nvme: new qemu nvme backend using nvme target · mlin@kernel.org (Ming Lin)
On Tue, 2015-12-01 at 17:02 +0100, Paolo Bonzini wrote:
On 01/12/2015 00:20, Ming Lin wrote:quoted
qemu-nvme: 148MB/s vhost-nvme + google-ext: 230MB/s qemu-nvme + google-ext + eventfd: 294MB/s virtio-scsi: 296MB/s virtio-blk: 344MB/s "vhost-nvme + google-ext" didn't get good enough performance.I'd expect it to be on par of qemu-nvme with ioeventfd but the question is: why should it be better? For vhost-net, the answer is that more zerocopy can be done if you put the data path in the kernel. But qemu-nvme is already using io_submit for the data path, perhaps there's not much to gain from vhost-nvme...
What do you think about virtio-nvme+vhost-nvme? I also have patch for vritio-nvme: https://git.kernel.org/cgit/linux/kernel/git/mlin/linux.git/log/?h=nvme-split/virtio Just need to change vhost-nvme to work with it.
Paoloquoted
Still tuning.