[tech] morwong NFS speed problem

[Alastair Irvine]

On Tue, 12 July, 2005 at 02:15:24PM +0800, Adrian Chadd wrote:
> Alastair: get some hard figures. "pretty crap" is very useless.
> Some throughputs with testing examples would be nice.

Fine.  (Although I should not have to justify myself here unless my
judgement counts for nothing.  I've been around long enough for "pretty
crap" to indicate something serious.)

  morwong% time cat {~50MiB file} > /dev/null
  0.006u 0.872s 12:04.65 0.1%     0+2k 5900+0io 0pf+0w

  mussel% time cat {~50MiB file} > /dev/null
  0.006u 0.364s 0:05.01 7.1%      0+0k 0+0io 0pf+0w

And also,

  mussel% time cat {~2MiB file} > /dev/null
  0.000u 0.014s 0:00.34 2.9%      0+0k 0+0io 0pf+0w

  morwong% time cat {~2MiB file} > /dev/null
  0.003u 0.053s 0:31.50 0.1%      0+2k 238+2io 1pf+0w

For those who haven't used the csh "time" command before, those first three
fields in the output are userspace time-in-seconds, kernel time-in-seconds
and elapsed time in minutes:seconds.  The sixth field is supposed to be
number of blocks read/written during I/O operations (I can't figure out why
this is 0 on Linux).

And for the record, the "pretty crap" measurement came from running mutt
on a ~8MiB mailbox.  It loaded very slowly on morwong and quickly on
mussel.

> 
> Specifically, the mounting is v3 nfs over TCP. This is good but it might
> not actually be optimal for this platform. There's plenty of space to
> tweak NFS. What you really need to come up with is an objective way
> of measuring "crap". :-)

-- 
... "What else is on?" "Yeah, let's see what else is on." "Where's the TV guide?"
               -- The 2 garage attendants, at the end of "The Truman Show"
 _____________________________________________________________________ 
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|  -=*Alastair Irvine*=-   <http://www.ucc.gu.uwa.edu.au/~alastair/>  |
|  C-monkey/wanderer/board&RPGer/net-nut  alastair at ucc.gu.uwa.edu.au  |
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