Thanks for the reply.
POPB MEM - 2Gb POPA MEM - 4Gb
Wireshark: (During a wget)
#tcp window size in the "bad" direction:
starts at win=6912 and grows to 165504 (This is where I start to see a heap of
TCP Dup ACK and TCP segment of a reassembled PDU)), then increases to 353408
(Again, more TCP Dup ACK's), and looks to max out at 669056.
#tcp window size in the "good" direction:
starts at win=6912 and looks to max out at 1995392 and has very few TCP Dup ACK
and TCP segment of a reassembled PDU
>
> Hi
>
> >Provider of the link is stating it is a tcp window issue
> I think that would be a bit weird, TCP is a very robust protocol
> capable to adapt pretty much any bandwidth / latency situations.
> What are the specifications on the hosts? Maybe POPA has too little
> RAM and can't allocate a big enough TCP window?
> Can you use wireshark or some other tool to capture the TCP segments
> and look at the advertised window?
>
> Greetings, Guido.
>
> On Fri, Apr 12, 2013 at 12:37 AM, John Elliot <johnellio...@hotmail.com>
> wrote:
> > Hi Guys,
> >
> >
> > I have a 40Mb connection between 2 POPs, and 2 Debian servers connected at
> > each end(L2, same broadcast domain) - I am seeing consistent poor
> > performance with TCP in only one direction.
> >
> >
> > Latency between the POP's is ~67m/sec
> >
> >
> > POPA->POPB UDP(IPERF) - consistent 38.5Mb/sec
> >
> > POPA->POPB TCP(IPERF) - fluctuates ~30Mb/sec -> 32Mb/sec
> >
> > POPA->POPB TCP(FTP) - fluctuates ~30Mb/sec -> 32Mb/sec
> >
> > POPA->POPB TCP(WGET) - fluctuates ~30Mb/sec -> 32Mb/sec
> >
> > POPB->POPA UDP(IPERF) - consistent 38.5Mb/sec
> >
> > POPB->POPA TCP(IPERF) - fluctuates ~10Mb/sec -> 15Mb/sec
> >
> > POPB->POPA TCP(FTP) - fluctuates ~10Mb/sec -> 15Mb/sec
> >
> > POPB->POPA TCP(WGET) - fluctuates ~10Mb/sec -> 15Mb/sec
> >
> >
> > Both Deb boxes are running the same kernel (2.6.32-5), and I have tried
> > adjusting tcp window without seeing any improvements...all ports are running
> > full duplex, and Im not seeing any errors/drops, nor packet-loss on the
> > link.
> >
> >
> > Any suggestions are greatly appreciated (Provider of the link is stating it
> > is a tcp window issue) -If that is the case, if someone can provide some
> > suggested tweaks/changes to the Deb servers, It would be fantastic!
> >
> > Cheers.
> >
> >
> >
> >
