Network performance issues when writing to disk (5.2.1-RELEASE)

David Burns david.burns at dugeem.net
Tue Aug 10 23:33:23 PDT 2004


Erik Rothwell wrote:

<snip>

> 
> When writing to a file, however:
> 
> # nc -l -p 2332 -vv | dd if=/dev/stdin of=/data/junk bs=1k
> listening on [any] 2332 ...
> connect to [192.168.5.1] from [192.168.5.3] 51296
>  sent 0, rcvd 1130496
> 1046+115 records in
> 1046+115 records out
> 1130496 bytes transferred in 32.888345 secs (34374 bytes/sec)
> 

You didn't mention what your hardware is... particularly disk IO 
controller...

If ata you could verify your disk is in a DMA mode - with "atacontrol 
mode 0" etc

One other possibility is PCI bus contention - particularly if the box 
has some ancient PCI implementation and/or slow memory.

Regards,
David


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