DCE SIGSEGV in LinuxSocketFdFactory

[Nat P]

Hi all,

the attached program gives me a sigsegv (it is basically a port of the standard tcp example under DCE). Can you try "at home" and see if, with default parameters, it crashes anyway?

Thank you

[Nat P]

The problem is caused by the fact that, in DCE, no application can start at time 0.0, because it can happen a condition between the socket creation code (it is scheduled an event at the 0.0 time in LinuxFdSocket) and the socket creation itself in the app.

Worth noticing it as a bug?

[Tommaso Pecorella]

Not a bug. A clarification in the docs maybe.

T.

[Hajime Tazaki]

Natale,

I can feel the issue you faced, but I can't run your example
with the following error.

what the codebase are you using ?

../myscripts/dce2-tcp-ns3-nsc-comparison.cc:400:74: error: 'TcpCubic' was not declared in this scope
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpCubic::GetTypeId ()));
^
../myscripts/dce2-tcp-ns3-nsc-comparison.cc:408:74: error: 'TcpHybla' was not declared in this scope
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpHybla::GetTypeId ()));
^
../myscripts/dce2-tcp-ns3-nsc-comparison.cc:416:74: error: 'TcpHighSpeed' was not declared in this scope
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpHighSpeed::GetTypeId ()));
^
../myscripts/dce2-tcp-ns3-nsc-comparison.cc:424:74: error: 'TcpBic' was not declared in this scope
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpBic::GetTypeId ()));
^
../myscripts/dce2-tcp-ns3-nsc-comparison.cc:428:74: error: 'TcpNoordwijk' was not declared in this scope
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpNoordwijk::GetTypeId ()));

I would like to see the solution (document or code) with the
working example.

thanks.

-- Hajime

At Mon, 16 Feb 2015 05:56:18 -0800 (PST),
Nat P wrote:
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[Nat P]

Il giorno lunedì 16 febbraio 2015 23:21:33 UTC+1, Hajime ha scritto:

Natale,

I can feel the issue you faced, but I can't run your example
with the following error.

what the codebase are you using ?

../myscripts/dce2-tcp-ns3-nsc-comparison.cc:400:74: error: 'TcpCubic' was not declared in this scope
       Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpCubic::GetTypeId ()));
                                                                          ^

You're right, I'm using the TCP flavors I've coded for Socis. You can comment any of them (keep alive the default ones, Westwood NewReno Tahoe).

> Not a bug. A clarification in the docs maybe.

That's a way... but this race condition (do you agree on naming?) means that a 1:1 port of simulations is impossible. I usually start all my simulations from Time(0.0) ... A possible way to fix this "feature" :-) could be a sort of "prioritization" of events, but I think this is rather difficult..