On 5/11/2010 1:01 PM, Hartmut Reuter wrote:
> 
> I have now ported AFS/RXOSD to 1.5.74.
> I am testing the client against servers running 1.4.12-osd.
> 
> My client configuration is memcache with chunksize 18 (256K).
> Writing to the fileserver and also to the rxosd is as fast as with the 1.4.12
> client (I am testing on my laptop with the whole test-cell in the laptop, so 
> 30
> MB/s is already an acceptable value).
> 
> But reading large files is terribly slow (~ 1 MB/s). With the 1.4.12 client 
> read
> and write have about the same speed.
> 
> with rxdebug -peer -long I can also see that some times in the rtt the
> fileserver or rxosd see is growing up to several seconds and then again going
> down to a ms. So there seems to be something strange in the rx-layer.
> It also shows a lot of resends (about 1 %).
> 
> Any idea?
> 
> Hartmut

The first thing that comes to mind is that we found the rx library was
dropping packets on the floor under high load.  This was fixed in the
1.5.74 release but has not been fixed in the 1.4.12 release.

The 1.5.74 client should be able to put more load on the file server
as it does a much better job of efficiently reading from the page
cache.

Jeffrey Altman

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

Reply via email to