[Virtio-fs] [QUESTION] A performance problem for buffer write compared with 9p

[Miklos Szeredi]

On Tue, Aug 20, 2019 at 11:16 AM Stefan Hajnoczi <stefanha at redhat.com> wrote:
>
> On Thu, Aug 15, 2019 at 08:30:43AM +0800, wangyan wrote:
> > Hi all,
> >
> > I met a performance problem when I tested buffer write compared with 9p.
>
> CCing Miklos, FUSE maintainer, since this is mostly a FUSE file system
> writeback question.

This is expected.   FUSE contains lots of complexity in the buffered
write path related to preventing DoS caused by the userspace server.

This added complexity, which causes the performance issue, could be
disabled in virtio-fs, since the server lives on a different kernel
than the filesystem.

I'll do a patch..

Thanks,
Miklos