From: Eric Dumazet <[EMAIL PROTECTED]> Date: Sat, 03 Dec 2005 02:25:53 +0100
> Note that on a router (ie most packets are not locally delivered), copybreak > is useless and expensive. > > But if most packets are locally delivered (on local TCP or UDP > queues), then copybreak is a win because less memory is taken by not > yet read packets in queues. > > Allocating a 256 bytes block instead of a full 4096 page if a 16 factor. > > For a machine doing some p2p trafic (ie receiving lot of small UDP frames or > handling a lot of TCP sockets), copybreak is definitly a good feature. > > So maybe an ethtool tune should be added to set the copybreak limit on each > nic. AFAIK tg3 uses a fixed size copybreak limit. I agree with the analysis, but I truly hate knobs. Every new one we add means it's even more true that you need to be a wizard to get a Linux box performing optimally. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
