Performance Intel Pro 1000 MT (PWLA8490MT)

Jin Guojun [VFFS] g_jin at lbl.gov
Tue Apr 19 20:55:48 PDT 2005


Bruce Evans wrote:

> On Tue, 19 Apr 2005, Bosko Milekic wrote:
>
>>  My experience with 6.0-CURRENT has been that I am able to push at
>>  least about 400kpps INTO THE KERNEL from a gigE em card on its own
>>  64-bit PCI-X 133MHz bus (i.e., the bus is uncontested) and that's
>
>
> A 64-bit bus doesn't seem to be essential for reasonable performance.
>
> I get about 210 kpps (receive) for a bge card on an old Athlon system
> with a 32-bit PCI 33MHz bus.  Overclocking this bus speeds up at least
> sending almost proportionally to the overclocking :-).  This is with
> my version of an old version of -current, with no mpsafenet, no driver
> tuning, and no mistuning (no INVARIANTS, etc., no POLLING, no HZ > 100).
> Sending goes slightly slower (about 200 kppps).

Yes, 64-bit is not essential for getting 400~700 Mbps as long as the system
has enough high memory bandwidth, but it is essential to get full Gigabits.

Simple numbers are in "Tips" section at the bottom of the following page:

    http://www-didc.lbl.gov/NCS/generic/ncs-00.html

and the details are described in the papers linked.

P.S.   Question the unit "kpps" used in original email. I am not sure 
what this really means.
           GigE is possible to produce 400 kpps if packet size is 300 
bytes or less.
           If packet size is 1500 byte, the maximum pps is 83k (83kpps).
           But, 200-400 kbps is kind low, maybe I missed some previous 
emails.

-- 
------------ Jin Guojun ----------- v --- jin at george.lbl.gov ---
Distributed Systems Department		http://www.dsd.lbl.gov/~jin
Lawrence Berkeley National Laboratory,	Berkeley, CA 94720



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