Re: nfs is slow

[Cameron Kerr <cameron.kerr@paradise.net.nz>]

On 15 Feb 2002, Andreas Leitner wrote:

>
>I am running a box with debian testing and one with woody. The testing
>acts as a nfs server and unstable as client. They are connected via a
>10MB hub - no real traffic, it's my home network. When I try to copy a
>file from a local dir to a nfs dir on the unstable box it is reaaaaly
>slow. midnight commander tells me it is copying with 23KB/s (copying a
>file of 1300MB takes forever). That cannot be right?

You should really include a couple of important options when you mount the
NFS filesystem on the client.

-- /etc/fstab --
foo:/home /home nfs rsize=8192,wsize=8192,yourotheroptions 0 0
----

Network transmissions are a funny thing. I wrote a program once that would
be use a changing buffer size, from 1 byte, doubling each time it was
called, to 1MB, the transfer speed made the most unusual shape, something
like

  |                 ---------------------------
  |               -
  |         -   -
  |       -   -
  |     -
  |   -
  |-
  +----------------------------------------------
   1B              4k 8k                      1MB

(This is very rusty, but you get the idea that the optimal buffer size is
4k or 8k). Stangely enough, I haven't been able to replicate the strange
dip...

Cameron Kerr
-- 
cameron.kerr@paradise.net.nz
http://homepages.paradise.net.nz/~cameronk/