Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Computing > Cisco > Network Performance 1GB ports

Reply
Thread Tools

Network Performance 1GB ports

 
 
Jasper Janssen
Guest
Posts: n/a
 
      11-19-2009
On Thu, 19 Nov 2009 19:03:05 +0100, "Tosh" <(E-Mail Removed)> wrote:
>> Try 'iperf -c ... -P n', where 'n' is the number of threads to run. The
>> man page
>> does say "The threading implementation is rather heinous", so who knows. A
>> quick
>> loopback test [ie client and server] on this quad core shows -P 3 to give
>> the
>> highest 'throughput' [19.2Gbps], which I suppose makes sense.
>>

>
>Did you try that in a real envoironment, I mean from host to host?
>There is something that I don't understand in that, in all my previous tests
>i've seen well clocked cpus jumping at 100% utilization with approx 400mbps
>( megabit x sec) of unidirectional iperf traffic, 20 gig is too far from
>those results to make sense to me, don't you agree?


It says he's using client and server on the same PC, which means that
probably the data isn't leaving the CPU, certainly not RAM, and should be
limited by the throughput of memory bus or better.

In host-to-host tests, it's usually the running of the actual network card
that costs the cpu utilization, not the generating of the data or
(apparently, according to this test) even the running of the IP stack.

Jasper
 
Reply With Quote
 
 
 
 
alexd
Guest
Posts: n/a
 
      11-19-2009
Meanwhile, at the comp.dcom.sys.cisco Job Justification Hearings, Tosh chose the
tried and tested strategy of:

> There is something that I don't understand in that, in all my previous tests
> i've seen well clocked cpus jumping at 100% utilization with approx 400mbps
> ( megabit x sec) of unidirectional iperf traffic, 20 gig is too far from
> those results to make sense to me, don't you agree?


Depends what is using the CPU. Could be iperf, could be the NIC driver, could be
the IP stack on the OS.

--
<http://ale.cx/> (AIM:troffasky) ((E-Mail Removed))
21:46:33 up 33 days, 2:05, 4 users, load average: 0.29, 0.23, 0.19
Plant food is a made up drug

 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Type of actual ports is not compatible with type of ports of entity. mreister VHDL 1 05-25-2010 11:30 AM
Recommendations Please for a PCI card w/ two USB 2 Ports and FireWaire Ports Mike Digital Photography 27 02-26-2006 12:54 AM
Newbie: Network Sockets and Ports boanator@optonline.net Java 5 05-11-2005 07:05 PM
testing ports through network Billy K Computer Security 5 05-30-2004 05:15 PM
Capacity of 1GB SanDisk Ultra vs 1GB Microdrive Graham Russell Digital Photography 8 11-23-2003 04:36 PM



Advertisments