PHWinfo - Afficher un message

06/03/2006, 19h14

hugopessotti@yahoo.com.br wrote:
> Im having problems with Opera browser with loading certain sites.
>
> While sniffing with Ethereal, I get a very very high count of "TCP Dup
> ACK" (and I mean a VERY HIGH count, the loading of Slashdot have more
> than 45k of it).
>
> Im pasting two lines of the log, if anyone can explain whats happening
> Im very grateful. (I cant paste the entire log here, its VERY long. But
> i can compress and upload it somewhere)
>
> 46488 161.837312 10.0.0.2 66.35.250.55 TCP
> [TCP Dup ACK 258#23057] 1209 > http [ACK] Seq=1313 Ack=3837 Win=32464
> Len=0
> 46489 161.843931 66.35.250.55 10.0.0.2 TCP
> [TCP Dup ACK 299#23047] http > 1209 [ACK] Seq=1662 Ack=1312 Win=16384
> Len=0
>
> ps. I received DupAcks for about 3 minutes with non-stop bandwidth of
> 8kb/s
> ps2. That happens in Linux also, but the log was captured in Windows
> ps3. It only happens with Opera.. Firefox and IE is everything ok
> ps4. Im not behind a firewall or something. My router is fully open to
> internet access
>
> Thanks in advance,
> Hugo
>

It happens to me too, on Linux using Firefox. Slashdot does it
quite often. I haven't timed how long it goes on for, but 3
minutes sounds about right. I get the impression that I get more
than 8Kb/s of it though. I guess the throughput is quite
sensitive to round trip time.

06/03/2006, 19h14	#3
Steve Horsley Messages: n/a Hébergeur:	Re: High TCP DupAck count hugopessotti@yahoo.com.br wrote: > Im having problems with Opera browser with loading certain sites. > > While sniffing with Ethereal, I get a very very high count of "TCP Dup > ACK" (and I mean a VERY HIGH count, the loading of Slashdot have more > than 45k of it). > > Im pasting two lines of the log, if anyone can explain whats happening > Im very grateful. (I cant paste the entire log here, its VERY long. But > i can compress and upload it somewhere) > > 46488 161.837312 10.0.0.2 66.35.250.55 TCP > [TCP Dup ACK 258#23057] 1209 > http [ACK] Seq=1313 Ack=3837 Win=32464 > Len=0 > 46489 161.843931 66.35.250.55 10.0.0.2 TCP > [TCP Dup ACK 299#23047] http > 1209 [ACK] Seq=1662 Ack=1312 Win=16384 > Len=0 > > ps. I received DupAcks for about 3 minutes with non-stop bandwidth of > 8kb/s > ps2. That happens in Linux also, but the log was captured in Windows > ps3. It only happens with Opera.. Firefox and IE is everything ok > ps4. Im not behind a firewall or something. My router is fully open to > internet access > > Thanks in advance, > Hugo > It happens to me too, on Linux using Firefox. Slashdot does it quite often. I haven't timed how long it goes on for, but 3 minutes sounds about right. I get the impression that I get more than 8Kb/s of it though. I guess the throughput is quite sensitive to round trip time.