Network stack cloning / virtualization patches

[Julian Elischer]

On Fri, 30 May 2003, Juli Mallett wrote:

> 
> Has anyone looked at making the patch work with CURRENT?  Does this do
> anything to degrade performance of UP systems with no (0?) virtualised
> images running?

I have been running tests between two machines with this patch
installed. There is a "per packet" overhead increase of about 1%.
there is no overhead increase in the per-byte overhead..
in ther words, sending 1 byte packets gets about a 1% decrease in
throughput but sending 8k chunks has almost no overhead increase..

Both my machines end up maxing out the 100Mb ethernet between them
before they see any speed difference at high packet sizes.


>  Does it make the locking situation much worse?  Can it
> be stripped down to minimal, clean, well-architected diffs to accomplish
> a centralised goal, rather than a "Network+goodies, random subsystem
> overhaul"?  

It is unlikely that the patches could be made in smaller orthogonal
patches. Its kind of "all or nothing".. Either everything is global or
it is in a structure (per VM).

> Those are probably good questions for someone to know the
> answers to (by looking at the code, or someone trying such) before it
> gets too close to the tree.




> 
> If this is your priority patch, hunting down someone with serious
> network\ stack-fu to review the diff, and whatnot, would probably be
> a good investment of your time in that regard.

I'll bepresenting Marco's paper at USENIX on the (ummm 12th I think).
His baby is due then so he can't make it..
(whereas mine arrived today so I'll be looking for an excuse to be away
from the house for 2 days ;-)
 

> 
> Thanx,
> juli.
> -- 
> juli mallett. email: jmallett at freebsd.org; efnet: juli;
> _______________________________________________
> freebsd-hackers at freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
> To unsubscribe, send any mail to "freebsd-hackers-unsubscribe at freebsd.org"
>