more weird bugs with mmap-ing via NFS

Mikhail Teterin mi+mx at
Tue Mar 21 23:58:52 UTC 2006

вівторок 21 березень 2006 18:48, Patrick M. Hausen Ви написали:
> On Tue, Mar 21, 2006 at 06:26:45PM -0500, Mikhail Teterin wrote:
> > The problem is about same with 32K and 16K packets. With 8K packets, the
> > thing kind-of works (although trying to `systat -vm' still stalls disk
> > access), but the outgoing traffic is over 20Mb/s on average -- MUCH more,
> > than the writing program itself generates.
> Are you using TCP or UDP for your NFS mounts?

I don't specify either, but the default is UDP, is not it?

> Now imagine a client that experiences this problem only
> sometimes. Modern hardware, but for some reason (network
> congestion?) some frames are still lost if sent back-to-back.
> (Realtek chipset on the receiving side?)

No, both sides have em-cards and are only separated by a rather decent large 

I'll try the TCP mount, workaround. If it helps, we can assume, our UDP NFS is 
broken for sustained high bandwidth writes :-(



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