[openib-general] How about ib_send_page() ?

[Jeff Carr]

Grant Grundler wrote:
> vmstat doesn't tell you where the time is being spent.
 >
> Get a profile or try out the beta Pentium M or AMD64 perfmon support

Yes, I would but I didn't think I could because I have Xeon's.

> You also want to explore "netperf -C" option that' available with
> netperf 2.4.0-rc1 (See www.netperf.orf).  I've posted results here
> before about binding netperf/netserver processes to different CPUs.

I think I remember this thread. I'll look back for it again.

It does look like the -C option is in 2.3.4 though:

root at delta:~# netperf -C -H foxtrot -- -s 105472 -r 105472
TCP STREAM TEST to foxtrot
Recv   Send    Send                          Utilization       Service 
Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local 
remote
bytes  bytes   bytes    secs.    10^6bits/s  % U      % T      us/KB   us/KB

  87380 210944 210944    10.00      2330.71   -1.00    89.49    -1.000 
3.146


Still, I'll look back for the thread on the subject.

> NAPI obsoletes interrupt coalescing to a large degree on regular NICs.

?

> But IPoIB can't really implement NAPI since it's sending work to
> a shared HCA. 

 > And any form of interrupt coalescing would interfere with
> any latency sensitive work as well (if present).

Surely. It would have to be configureable for people (like me) that 
wanted it. I don't care about latency, just about throughput. What's the 
point of having a fast network if you can't send *lots* of data over it. :)

Jeff