Jumbo Frames with em

[Gleb Smirnoff]

On Sun, Sep 03, 2006 at 08:46:21PM -0500, Derrick T. Woolworth wrote:
D> I'm running -current on a NFS file server with a 3ware controller
D> striping across multiple disks.  The box uses the em driver with the
D> mtu set to 8192 - client machines connecting via NFS that are also
D> running -current with bge drivers with the mtu set to 8192 (and jumbo
D> frames enabled on the switch)...
D> 
D> The em driver's README says that UDP and Jumbo Frames don't play well
D> together - just wondering if this would have any impact on NFS over
D> TCP?

This comment is quite old. It may happen that this isn't true anymore.
May be developers from Intel will comment on this.

D> Does anyone know anything about the future of the em driver or
D> bge driver that might have performance issues with Jumbo Frames?
D> 
D> I'm only ever seeing the storage system write about 10 to 15MB (bytes)
D> per second over NFS.

Have you tested the performance with ftp, netcat or some network
benchmarking tool? The problem may be in NFS not in driver.

-- 
Totus tuus, Glebius.
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