[OpenAFS] strange disk write activity compared to network bandwidth

[Jeffrey Altman]

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Sophana wrote:
> Hi
> 
> I'm evaluating openafs 1.4.4 performance on centos 4
> I noticed some strange things.
> 
> I'm doing a simple svn checkout (meaning write to afs) (server on the
> lan)  of a lot of source files (quite small...) (about 50mbyte+svn
> overhead ~= 100mbyte)
> When using gkrellm, I can see the disk write bandwidth at at a high
> level (> 15mbyte/s), almost no read, and the network bandwidth is MUCH
> lower (less than 1mbyte/s). It seem that the server is busy making a LOT
> of disk writes, that are about 10 to 20 times the volume of the real
> data being written.

This is only a guess but for every change to a directory the new
directory contents will be written to disk.  This is in addition to the
data belonging to the files.


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