Re: Actual window sized used
I did some monitoring with Windows Network Monitor today to try to confirm
iperfs behavior. First I removed the registry edits that I had made
previously, essentially setting Windows back to it's default behavior. The
key removed were:
GlobalMaxTcpWindowSize=17520
Tcp1323Opts=1
TcpWindowSize=17520
I then ran iperf with the following params:
server
iperf -s -p 5001 -w 17520
client
iperf -w 17520 -n 100M -p 5001 -c server06
On both the client & server, iperf reported that it was using the requested
TCP window size. However, the packets captured in Network Monitor showed
that a window size of 64240 was being used. Which one is correct?
Thanks
----- Original Message -----
From: "William E. Allcock" <allcock --at-- mcs.anl.gov>
To: <iperf-users --at-- dast.nlanr.net>
Sent: Friday, September 09, 2005 4:43 PM
Subject: Re: Actual window sized used
> That is true for the default, but iperf can not override the maximum
> value set.
>
> Bill
>
> McConnell Andrew (CDI) wrote:
> > Whatever window size you set on iperf's command line will override the
> > OS setting. If you don't specify a window using -w then iperf will use
> > the window size your OS specifies.
> >
> > --Andy
> >
> >
> > -----Original Message-----
> > From: owner-iperf-users --at-- dast.nlanr.net
> > [mailto:owner-iperf-users --at-- dast.nlanr.net] On Behalf Of Chris McFarling
> > Sent: Friday, September 09, 2005 11:28 AM
> > To: iperf-users --at-- dast.nlanr.net
> > Subject: Actual window sized used
> >
> > Do TCP window parameter settings in the OS affect the window size used
> > by
> > iperf? For example, if I make the following registry edits in Win2K:
> >
> > GlobalMaxTcpWindowSize=17520
> > Tcp1323Opts=1
> > TcpWindowSize=17520
> >
> > and the start iperf with the following:
> >
> > iperf -s -w 65700
> >
> >
> > will iperf use a 65700 byte window or will it use a 17520 window? It
> > reports
> > that is using a window size of 64K but I just want to verify that what
> > it's
> > reporting is actually true.
> >
> > Thanks
> >
> >
> >
> >
>
> --
> William E. Allcock
> Argonne National Laboratory
> Bldg 221, Office C-115A
> 9700 South Cass Ave
> Argonne, IL 60439-4844
> Office Phone: +1-630-252-7573
> Office Fax: +1-630-252-1997
> Cell Phone: +1-630-854-2842
>
>