Re: [2.6.30.1] Significant latency playing video file from NFS4 share

public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed

From: Frans Pop <elendil@planet.nl>
To: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: linux-nfs@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	netdev@vger.kernel.org
Subject: Re: [2.6.30.1] Significant latency playing video file from NFS4 share
Date: Tue, 21 Jul 2009 19:31:48 +0200	[thread overview]
Message-ID: <200907211931.50015.elendil@planet.nl> (raw)
In-Reply-To: <200907180131.12586.elendil@planet.nl>

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset="utf-8", Size: 7976 bytes --]

Any suggestions based on the data below?
Is the problem maybe that the amount of data transferred each time is sobig that the network speed becomes a bottleneck and causes the latency?I can reproduce the issue with both a 10MBit wired link and with a 54MBitwireless link.
Is this a kernel bug or a configuration issue?
Thanks,FJP
On Saturday 18 July 2009, Frans Pop wrote:> Thanks for the quick response!>> On Saturday 18 July 2009, Trond Myklebust wrote:> > Have you tried running nfs-iostat from the nfs-utils package to try> > and figure out what the latency is on each READ request from the> > client?> >> > You need to run something like> >> >     nfs-iostat --page 20 10 /src/<mountpoint>> >> > while running the vlc app.
$ ../nfs-iostat.py --page 20 10 /srv/fjp/david
Note:The mount point selection could be improved. I first had a trailing slashafter the mount point and that resulted in all mounts being included in theoutput. Removing the slash helped.
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.65 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.406 Â  Â  Â  Â  101.661 Â  Â  Â  Â  250.613 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  1211.745 Â  Â  Â  Â 1222.640write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
13 nfs_readpage() calls read 13 pages1417 nfs_readpages() calls read 971428 pages (685.6 pages per call)
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages18760 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.25 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.100 Â  Â  Â  Â  Â  0.426 Â  Â  Â  Â  Â  4.262 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  6.000 Â  Â  Â  Â  Â  6.000write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages2 nfs_readpages() calls read 2 pages (1.0 pages per call)
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages6 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.80 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.750 Â  Â  Â  Â  192.196 Â  Â  Â  Â  256.262 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  1998.933 Â  Â  Â  Â 1999.200write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages1 nfs_readpages() calls read 960 pages (960.0 pages per call)
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages6 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.00 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages0 nfs_readpages() calls read 0 pages
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages6 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.85 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.750 Â  Â  Â  Â  192.196 Â  Â  Â  Â  256.262 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  1927.467 Â  Â  Â  Â 1927.467write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages1 nfs_readpages() calls read 960 pages (960.0 pages per call)
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages6 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.00 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages0 nfs_readpages() calls read 0 pages
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages6 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.85 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.750 Â  Â  Â  Â  192.196 Â  Â  Â  Â  256.262 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  1930.933 Â  Â  Â  Â 1931.467write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages1 nfs_readpages() calls read 960 pages (960.0 pages per call)
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages5 nfs_writepages() calls wrote 0 pages (0.0 pages per call)
elrond:/david mounted on /srv/fjp/david:
Â  Â op/s Â  Â  Â  Â  rpc bklogÂ  Â 0.15 Â  Â  Â  Â  Â  Â 0.00read: Â  Â  Â  Â  Â  Â  ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.100 Â  Â  Â  Â  Â  0.426 Â  Â  Â  Â  Â  4.262 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  6.000 Â  Â  Â  Â  Â  6.000write: Â  Â  Â  Â  Â  Â ops/s Â  Â  Â  Â  Â  Â kB/s Â  Â  Â  Â  Â  kB/op Â  Â  Â  Â  retrans Â  Â  Â  Â  avg RTT (ms) Â  Â avg exe (ms)Â  Â  Â  Â  Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â 0 (0.0%) Â  Â  Â  Â  Â  0.000 Â  Â  Â  Â  Â  0.000
0 nfs_readpage() calls read 0 pages2 nfs_readpages() calls read 2 pages (1.0 pages per call)
0 nfs_updatepage() calls0 nfs_writepage() calls wrote 0 pages6 nfs_writepages() calls wrote 0 pages (0.0 pages per call)ÿôèº{.nÇ+‰·Ÿ®‰†+%ŠËÿ±éÝ¶\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dÊ‡Ú™ë,j\a¢f£¢·hšïêÿ‘êçz_è®\x03(éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨èÚ&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

next prev parent reply	other threads:[~2009-07-21 17:31 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-17 20:50 [2.6.30.1] Significant latency playing video file from NFS4 share Frans Pop
2009-07-17 22:51 ` Trond Myklebust
2009-07-17 23:31   ` Frans Pop
2009-07-21 17:31     ` Frans Pop [this message]
2009-07-21 17:58       ` Trond Myklebust
2009-07-21 21:54         ` Frans Pop

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=200907211931.50015.elendil@planet.nl \
    --to=elendil@planet.nl \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nfs@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=trond.myklebust@fys.uio.no \
    /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