From: Christian Schoenebeck <qemu_oss@crudebyte.com>
To: qemu-devel@nongnu.org
Cc: Vivek Goyal <vgoyal@redhat.com>,
"Venegas Munoz,
Jose Carlos" <jose.carlos.venegas.munoz@intel.com>,
"cdupontd@redhat.com" <cdupontd@redhat.com>,
virtio-fs-list <virtio-fs@redhat.com>,
Stefan Hajnoczi <stefanha@redhat.com>,
"Shinde, Archana M" <archana.m.shinde@intel.com>,
"Dr. David Alan Gilbert" <dgilbert@redhat.com>
Subject: Re: virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance)
Date: Tue, 29 Sep 2020 15:59:34 +0200 [thread overview]
Message-ID: <6044656.UxkCsAYsKb@silver> (raw)
In-Reply-To: <20200929134942.GC220516@redhat.com>
On Dienstag, 29. September 2020 15:49:42 CEST Vivek Goyal wrote:
> > Depends on what's randomized. If read chunk size is randomized, then yes,
> > you would probably see less performance increase compared to a simple
> > 'cat foo.dat'.
>
> We are using "fio" for testing and read chunk size is not being
> randomized. chunk size (block size) is fixed at 4K size for these tests.
Good to know, thanks!
> > If only the read position is randomized, but the read chunk size honors
> > iounit, a.k.a. stat's st_blksize (i.e. reading with the most efficient
> > block size advertised by 9P), then I would assume still seeing a
> > performance increase.
>
> Yes, we are randomizing read position. But there is no notion of looking
> at st_blksize. Its fixed at 4K. (notice option --bs=4k in fio
> commandline).
Ah ok, then the results make sense.
With these block sizes you will indeed suffer a performance issue with 9p, due
to several thread hops in Tread handling, which is due to be fixed.
Best regards,
Christian Schoenebeck
next prev parent reply other threads:[~2020-09-29 14:01 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-18 21:34 tools/virtiofs: Multi threading seems to hurt performance Vivek Goyal
2020-09-21 8:39 ` Stefan Hajnoczi
2020-09-21 13:39 ` Vivek Goyal
2020-09-21 16:57 ` Stefan Hajnoczi
2020-09-21 8:50 ` Dr. David Alan Gilbert
2020-09-21 13:35 ` Vivek Goyal
2020-09-21 14:08 ` Daniel P. Berrangé
2020-09-21 15:32 ` Dr. David Alan Gilbert
2020-09-22 10:25 ` Dr. David Alan Gilbert
2020-09-22 17:47 ` Vivek Goyal
2020-09-24 21:33 ` Venegas Munoz, Jose Carlos
2020-09-24 22:10 ` virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance) Vivek Goyal
2020-09-25 8:06 ` virtiofs vs 9p performance Christian Schoenebeck
2020-09-25 13:13 ` Vivek Goyal
2020-09-25 15:47 ` Christian Schoenebeck
2021-02-19 16:08 ` Can not set high msize with virtio-9p (Was: Re: virtiofs vs 9p performance) Vivek Goyal
2021-02-19 17:33 ` Christian Schoenebeck
2021-02-19 19:01 ` Vivek Goyal
2021-02-20 15:38 ` Christian Schoenebeck
2021-02-22 12:18 ` Greg Kurz
2021-02-22 15:08 ` Christian Schoenebeck
2021-02-22 17:11 ` Greg Kurz
2021-02-23 13:39 ` Christian Schoenebeck
2021-02-23 14:07 ` Michael S. Tsirkin
2021-02-24 15:16 ` Christian Schoenebeck
2021-02-24 15:43 ` Dominique Martinet
2021-02-26 13:49 ` Christian Schoenebeck
2021-02-27 0:03 ` Dominique Martinet
2021-03-03 14:04 ` Christian Schoenebeck
2021-03-03 14:50 ` Dominique Martinet
2021-03-05 14:57 ` Christian Schoenebeck
2020-09-25 12:41 ` virtiofs vs 9p performance(Re: tools/virtiofs: Multi threading seems to hurt performance) Dr. David Alan Gilbert
2020-09-25 13:04 ` Christian Schoenebeck
2020-09-25 13:05 ` Dr. David Alan Gilbert
2020-09-25 16:05 ` Christian Schoenebeck
2020-09-25 16:33 ` Christian Schoenebeck
2020-09-25 18:51 ` Dr. David Alan Gilbert
2020-09-27 12:14 ` Christian Schoenebeck
2020-09-29 13:03 ` Vivek Goyal
2020-09-29 13:28 ` Christian Schoenebeck
2020-09-29 13:49 ` Vivek Goyal
2020-09-29 13:59 ` Christian Schoenebeck [this message]
2020-09-29 13:17 ` Vivek Goyal
2020-09-29 13:49 ` [Virtio-fs] " Miklos Szeredi
2020-09-29 14:01 ` Vivek Goyal
2020-09-29 14:54 ` Miklos Szeredi
2020-09-29 15:28 ` Vivek Goyal
2020-09-25 12:11 ` tools/virtiofs: Multi threading seems to hurt performance Dr. David Alan Gilbert
2020-09-25 13:11 ` Vivek Goyal
2020-09-21 20:16 ` Vivek Goyal
2020-09-22 11:09 ` Dr. David Alan Gilbert
2020-09-22 22:56 ` Vivek Goyal
2020-09-23 12:50 ` [Virtio-fs] " Chirantan Ekbote
2020-09-23 12:59 ` Vivek Goyal
2020-09-25 11:35 ` Dr. David Alan Gilbert
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6044656.UxkCsAYsKb@silver \
--to=qemu_oss@crudebyte.com \
--cc=archana.m.shinde@intel.com \
--cc=cdupontd@redhat.com \
--cc=dgilbert@redhat.com \
--cc=jose.carlos.venegas.munoz@intel.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
--cc=vgoyal@redhat.com \
--cc=virtio-fs@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).