Re: bdflush/rpciod high CPU utilization, profile does not makesense

From: Trond Myklebust
Date: Tue Apr 19 2005 - 17:53:31 EST


ty den 19.04.2005 Klokka 21:45 (+0200) skreiv Jakob Oestergaard:

> It mounts a home directory from a 2.6.6 NFS server - the client and
> server are on a hub'ed 100Mbit network.
>
> On the earlier 2.6 client I/O performance was as one would expect on
> hub'ed 100Mbit - meaning, not exactly stellar, but you'd get around 4-5
> MB/sec and decent interactivity.

OK, hold it right there...

So, IIRC the problem was that you were seeing abominable retrans rates
on UDP and TCP, and you are using a 100Mbit hub rather than a switch?

What does the collision LED look like, when you see these performance
problems?
Also, does that hub support NICs that do autonegotiation? (I'll bet the
answer is "no").

Cheers,
Trond

--
Trond Myklebust <trond.myklebust@xxxxxxxxxx>

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