[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems
From: |
Christian Schoenebeck |
Subject: |
Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance) |
Date: |
Fri, 25 Sep 2020 18:33:08 +0200 |
On Freitag, 25. September 2020 18:05:17 CEST Christian Schoenebeck wrote:
> On Freitag, 25. September 2020 15:05:38 CEST Dr. David Alan Gilbert wrote:
> > > > 9p ( mount -t 9p -o trans=virtio kernel /mnt
> > > > -oversion=9p2000.L,cache=mmap,msize=1048576 ) test: (g=0): rw=randrw,
> > >
> > > Bottleneck ------------------------------^
> > >
> > > By increasing 'msize' you would encounter better 9P I/O results.
> >
> > OK, I thought that was bigger than the default; what number should I
> > use?
>
> It depends on the underlying storage hardware. In other words: you have to
> try increasing the 'msize' value to a point where you no longer notice a
> negative performance impact (or almost). Which is fortunately quite easy to
> test on guest like:
>
> dd if=/dev/zero of=test.dat bs=1G count=12
> time cat test.dat > /dev/null
I forgot: you should execute that 'dd' command and host side, and the 'cat'
command on guest side, to avoid any caching making the benchmark result look
better than it actually is. Because for finding a good 'msize' value you only
care about actual 9p data really being transmitted between host and guest.
Best regards,
Christian Schoenebeck
- Re: tools/virtiofs: Multi threading seems to hurt performance, (continued)
- Re: tools/virtiofs: Multi threading seems to hurt performance, Vivek Goyal, 2020/09/22
- Re: tools/virtiofs: Multi threading seems to hurt performance, Venegas Munoz, Jose Carlos, 2020/09/24
- virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Vivek Goyal, 2020/09/24
- Re: virtiofs vs 9p performance, Christian Schoenebeck, 2020/09/25
- Re: virtiofs vs 9p performance, Vivek Goyal, 2020/09/25
- Re: virtiofs vs 9p performance, Christian Schoenebeck, 2020/09/25
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Dr. David Alan Gilbert, 2020/09/25
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Christian Schoenebeck, 2020/09/25
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Dr. David Alan Gilbert, 2020/09/25
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Christian Schoenebeck, 2020/09/25
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance),
Christian Schoenebeck <=
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Dr. David Alan Gilbert, 2020/09/25
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Christian Schoenebeck, 2020/09/27
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Vivek Goyal, 2020/09/29
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Christian Schoenebeck, 2020/09/29
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Vivek Goyal, 2020/09/29
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Christian Schoenebeck, 2020/09/29
- Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Vivek Goyal, 2020/09/29
- Re: [Virtio-fs] virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Miklos Szeredi, 2020/09/29
- Re: [Virtio-fs] virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Vivek Goyal, 2020/09/29
- Re: [Virtio-fs] virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance), Miklos Szeredi, 2020/09/29