perfSONAR User Q&A and Other Discussion

[Gerry Creager <>]

You're getting pretty good results for a Broadcom NIC. I tend to spec 
Intel exclusively because of uniform poor performance with Broadcoms..

gerry

On 02/14/2012 01:43 PM, Joseph Bernard wrote:
> Broadcom NetXtreme BCM5721
>
>
> On 2/14/12 2:30 PM, "Brian 
> Tierney"<>
>   wrote:
>
> > interesting.
> >
> > what type of NIC is in this host?
> >
> >
> > On Feb 14, 2012, at 11:20 AM, Joseph Bernard wrote:
> >
> > > One more thing I've noticed.  When I do TCP in PS-PS, the server side
> > > CPU
> > > gets to 80%.  When I do UDP, the CPU only gets to 45%.  On CentOS 5.7,
> > > the
> > > CPU goes to 20% on TCP and 99% on UDP.
> > >
> > >
> > > Thanks,
> > > Joseph
> > >
> > >
> > > On 2/14/12 11:30 AM, "Joseph 
> > > Bernard"<>
> > >   wrote:
> > >
> > > > I used the -w option and got closer to 700Mb/s. I even put it at 64M to
> > > > see if it made a difference.  I decided to install CentOS 5.7 i386 and
> > > > got
> > > > 950Mb/s on both TCP and UDP, and the limit with the -w option is 256
> > > > Kbyte.  Now I'm not sure if PS-PS is slower or if CentOS 5.7 is less
> > > > accurate.
> > > >
> > > >
> > > > Thanks,
> > > > Joseph
> > > >
> > > >
> > > >
> > > >
> > > > On 2/13/12 5:13 PM, "Brian 
> > > > Tierney"<>
> > > >   wrote:
> > > >
> > > > > Did you use the -w option with UDP?
> > > > >
> > > > > TCP autotunes, UDP does not, and to go fast UDP needs more buffer
> > > > > space
> > > > > than the default.
> > > > >
> > > > > Try adding "-w 4M" to both sender and receiver.
> > > > >
> > > > > On Feb 13, 2012, at 1:35 PM, Joseph Bernard wrote:
> > > > >
> > > > > > I loaded 3.2.1.1 on 2 workstations and got 950Mb/s on TCP and 600Mb/s
> > > > > > on
> > > > > > UDP tests.  They both have 1Gb/s cards.  I thought maybe the network
> > > > > > cards
> > > > > > weren't up to snuff, so I got 2 HP servers, loaded them up, and did
> > > > > > the
> > > > > > same tests.  I got the same results.  The workstations/servers are
> > > > > > connected via crossover.  I even tried a brand new cable to be sure
> > > > > > it
> > > > > > wasn't bad materials.
> > > > > >
> > > > > > When I used my iMac and Macbook Pro from 2009 running Snow Leopard, I
> > > > > > was
> > > > > > able to get 800Mb/s running iperf.  Is there something I am missing?
> > > > > >
> > > > > >
> > > > > > Thanks,
> > > > > > Joseph Bernard