Analysing traces for performance bottlenecks

rcheung at rcheung at
Tue Jul 15 21:40:39 UTC 2008

Wireshark can show the throughput on a bits/sec or pps, by IP, etc. This is under IO Graphs. You'll want to change the time display format of the main decode window to Seconds Since Beginning of Capture to sync up time with the graph.

At least that way, you can just focus on the dips in throughput in the graphs.

---- Kevin Oberman <oberman at> wrote: 
> > Date: Tue, 15 Jul 2008 11:05:34 +0100
> > From: Sam Stickland <sam_mailinglists at>
> > 
> > Hi,
> > 
> > Are there any packages (or Wireshark options that I've missed) that can 
> > follow a TCP stream and determine the limiting factor on throughput. E.g 
> > Latency, packet loss, out of sequence packets, window size, or even just 
> > the senders rate onto the wire. I know how to analyse a trace by hand 
> > for performance issues, but it's relatively time consuming.
> > 
> > Googling for variations on "Analyse TCP stream limit throughput" didn't 
> > find anything.
> tcptrace is old and pretty basic, but it can provide a LOT if
> information. Combined with xplot, the graphs often point to the exact
> nature of a TCP problem, but you need a really good understanding of TCP
> to figure anything out.
> -- 
> R. Kevin Oberman, Network Engineer
> Energy Sciences Network (ESnet)
> Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
> E-mail: oberman at			Phone: +1 510 486-8634
> Key fingerprint:059B 2DDF 031C 9BA3 14A4  EADA 927D EBB3 987B 3751

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