SMC 8624T 24-port 10/100/1000 switch

Greg Lindahl lindahl at
Wed Nov 13 14:28:43 EST 2002

On Wed, Nov 13, 2002 at 09:39:24AM -0800, Paul English wrote:

> The Dell one does. I'm using it with jumbo frames right now. Of course it 
> looks like there may be a latency increase with jumbo frames - can anyone 
> confirm that? 

All gigabit switches are store-and-forward, so the maximum delay at
1500 MTU is 15 usec, 9000 MTU is 90 usec. Both of these are
significantly smaller than the overhead in Linux dealing with TCP,
which gets relatively better with jumbo frames.

But it all depends on what size your messages are, and exactly what
TCP does with them.

-- greg

Beowulf mailing list, Beowulf at
To change your subscription (digest mode or unsubscribe) visit

More information about the Beowulf mailing list