ANNOUNCEMENT: Live Wireshark University & Allegro Packets online APAC Wireshark Training Session
April 17th, 2024 | 14:30-16:00 SGT (UTC+8) | Online

Wireshark-dev: Re: [Wireshark-dev] Memory consumption in tshark

From: Evan Huus <eapache@xxxxxxxxx>
Date: Tue, 27 Aug 2013 16:37:27 -0400
We already discard a great deal of state in (single-pass) tshark that we keep around in Wireshark (or two-pass tshark). We do need to keep some, though. It's only a bug if we're keeping more than we actually need, and that's not determinable from the information we have here. Dario, if you could get us a memory profile of tshark in this situation (through valgrind's massif tool, for example) that would help us debug further.

I dislike the idea of two-pass by default for exactly this reason: people expect tshark to be relatively state-less. This is already not the case, but it's a lot worse in two-pass mode. It might even make sense to add a --state-less flag to tshark that disables all options which require state. I don't know how feasible that would be however.

Evan


On Tue, Aug 27, 2013 at 4:26 PM, Joerg Mayer <jmayer@xxxxxxxxx> wrote:
On Tue, Aug 27, 2013 at 06:53:01PM +0200, Jakub Zawadzki wrote:
> >> ./tshark -r traffic.all -Y "dns.qry.name.len > 50" -w longnames.pcap
> >
> >> Used memory grows continuously, up to over 3GB of ram. At this point my pc goes thrashing and I must kill tshark.
> >> That's not what I expected. I expected the memory to grow up to a certain size, then stop, feeding the output file.
> >> Any idea about what happens? Any suggestion on how to debug it?
>
> On Tue, Aug 27, 2013 at 02:40:07PM +0000, Anders Broman wrote:
>
> > No it will not; as state and stuff accumulates memory grows until *shark runs out of memory your mileage on
>
> Isn't it a bug? Do we need some special option for such case, or reusing
> single pass tshark is good enough?
> We should anyway do -2 pass default where we have a file (and not pipe).

IMO it's a bug. While we need to keep a lot of state for Wireshark, we don't need
(most of) it for tshark.

 Ciao
      Jörg

--
Joerg Mayer                                           <jmayer@xxxxxxxxx>
We are stuck with technology when what we really want is just stuff that
works. Some say that should read Microsoft instead of technology.
___________________________________________________________________________
Sent via:    Wireshark-dev mailing list <wireshark-dev@xxxxxxxxxxxxx>
Archives:    http://www.wireshark.org/lists/wireshark-dev
Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev
             mailto:wireshark-dev-request@xxxxxxxxxxxxx?subject=unsubscribe