[lkml]   [2002]   [Sep]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Early SPECWeb99 results on 2.5.33 with TSO on e1000

On Thu, 5 Sep 2002, Nivedita Singhvi wrote:

> > value in your results is in saving on retransmits; I would think
> > shoving the data down the NIC and avoid the fragmentation shouldnt
> > give you that much significant CPU savings. Do you have any stats
> Why do say that? Wouldnt the fact that youre now reducing the
> number of calls down the stack by a significant number provide
> a significant saving?

I am not sure; if he gets a busy system in a congested network, i can
see the offloading savings i.e i am not sure if the amortization of the
calls away from the CPU is sufficient enough savings if it doesnt
involve a lot of retransmits. I am also wondering how smart this NIC
in doing the retransmits; example i have doubts if this idea is briliant
to begin with; does it handle SACKs for example? What about
the du-jour algorithm, would you have to upgrade the NIC or can it be
taught some new trickes etc etc.
[also i can see why it makes sense to use this feature only with sendfile;
its pretty much useless for interactive apps]

Troy, i am not interested in the nestat -s data rather the TCP stats
this NIC has exposed. Unless those somehow show up magically in netstat.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:28    [W:0.312 / U:1.360 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site