Ubuntu and magic mini-trampolines (crash problem)

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

Ubuntu and magic mini-trampolines (crash problem)

Willem Huisman
F.Y.I.

OpenSim 0.6.4.9332
Debian Lenny 5.0.1
Mono JIT compiler version 20090414
(tarball Mon Apr 27 13:11:24 CEST 2009)

Compiled and installed  Mono from source recently. One thing I noticed
during  the 'make install', albeit it in a flash on screen, is that there
were compilation warnings during the use of mini-trampoline.cs ( don't
remember specific names ) where ".... type was declared but it's value is never used".

The mini-trampoline error/crash while starting opensim always happens when
 the section of scripts starts. Never happens earlier. I mean , the crash , in my case
with XEngine , always occurs at [XEngine] NameScriptLoading . After these crashes I
also noticed shutting down all of UGAIM and restarting them, made the crash 'stay away'.

As I type I am starting and shutting down to reproduce the crash. I will check Mantis if
I can add debug info , if any at all.

My efforts till now to backtrace with gdb have been unsuccesful. There are no debugging symbols for opensim,
or better, I do not know how to create/obtain them. Tried to hook gdb to the opensim' pid-id, but that stalls the running
opensim instance completely.

Maybe I should reinstall Mono and catch the warnings of the types of mini-trampolines.cs .. :S

----- Original Message -----
From: "Mic Bowman"
To: [hidden email]
Subject: Re: [Opensim-users] Ubuntu and magic mini-trampolines (crash problem)
Date: Tue, 28 Apr 2009 08:16:10 -0700


in general we see crashes, not freezes. the apparent freeze is usually
caused by the gdb process that gets started when the crash occurs
(kill the gdb process and the simulator crashes "gracefully").

given that the problem seems to happen when log4net attempts to get a
logger associated with a particular script class, my guess is that one
of a couple problems is happening... 1) mono is somehow messing up the
class that is passed in (there are nulls in the argument stack that
look suspicious), 2) log4net isn't as thread-safe as it claims (though
the routine that creates the wrapper object looks fine at first
glance), 3) somehow mono is screwing up the assembly binding when
log4net creates the wrapper. I've looked at the mono code that is
throwing the exception... but it wasn't very helpful without a LOT
more investigation.

at this point, i'm building a custom log4net dll with some additional
debugging in it. which, given that this certainly appears to be a
timing issue, will almost certainly hide the problem. :-(

--mic


On Tue, Apr 28, 2009 at 5:04 AM, Dr Scofield
wrote:
> Mic Bowman wrote:
>> we've seen the problem with mono_threads_per_cpu set across a range of
>> values (i think we've tried a number of values from 100 to 1000).
>> there doesn't appear to be any correlation.
>
> ok. we had freezes that got cured by increasing MONO_THREADS_PER_CPU, hence
> my
> asking...
>
> a real deadlock is nasty... :-( sigh.
>
>        DrS/dirk
>>
>> --mic
>>
>>
>> On Mon, Apr 27, 2009 at 10:38 PM, dr scofield
>> wrote:
>>> Justin Clark-Casey wrote:
>>>
>>> Mic Bowman wrote:
>>>
>>>
>>> I have the same freeze at times. In my case there's a gdb process
>>> running that I can kill off to terminate the simulator.
>>>
>>>
>>>
>>> I presume there's no revealing deadlock information in the thread dump
>>> (perhaps that's too much to hope for :) ?
>>>
>>>
>>> what is your value of the MONO_THREADS_PER_CPU environment variable?
>>>
>>> --
>>> dr dirk husemann ---- math & computer science ---- ibm zurich research lab
>>> RL: [hidden email] - +41 44 724 8573 - http://www.zurich.ibm.com/~hud/
>>> SL: [hidden email] --------------------- http://xyzzyxyzzy.net/
>>>
>>> _______________________________________________
>>> Opensim-users mailing list
>>> [hidden email]
>>> https://lists.berlios.de/mailman/listinfo/opensim-users
>>>
>>>
>> _______________________________________________
>> Opensim-users mailing list
>> [hidden email]
>> https://lists.berlios.de/mailman/listinfo/opensim-users
>>
>
>
> --
> dr dirk husemann ---- virtual worlds research ---- ibm zurich research lab
> SL: dr scofield ---- [hidden email] ---- http://xyzzyxyzzy.net/
> RL: [hidden email] - +41 44 724 8573 - http://www.zurich.ibm.com/~hud/
> _______________________________________________
> Opensim-users mailing list
> [hidden email]
> https://lists.berlios.de/mailman/listinfo/opensim-users
>
_______________________________________________
Opensim-users mailing list
[hidden email]
https://lists.berlios.de/mailman/listinfo/opensim-users



__________
WiLLuMPJuH

--
It's News. It's Reviews. It's Interviews. It's Free. What Are You Waiting For?
www.movieline.com!

_______________________________________________
Opensim-users mailing list
[hidden email]
https://lists.berlios.de/mailman/listinfo/opensim-users
Reply | Threaded
Open this post in threaded view
|

Re: Ubuntu and magic mini-trampolines (crash problem)

Kyle Hamilton
When you attach gdb to a running process, you need to use the 'cont'
command to have gdb continue the process.

-Kyle H

On Tue, Apr 28, 2009 at 9:06 AM, Willem Huisman
<[hidden email]> wrote:

> F.Y.I.
>
> OpenSim 0.6.4.9332
> Debian Lenny 5.0.1
> Mono JIT compiler version 20090414
> (tarball Mon Apr 27 13:11:24 CEST 2009)
>
> Compiled and installed  Mono from source recently. One thing I noticed
> during  the 'make install', albeit it in a flash on screen, is that there
> were compilation warnings during the use of mini-trampoline.cs ( don't
> remember specific names ) where ".... type was declared but it's value is
> never used".
>
> The mini-trampoline error/crash while starting opensim always happens when
>  the section of scripts starts. Never happens earlier. I mean , the crash ,
> in my case
> with XEngine , always occurs at [XEngine] NameScriptLoading . After these
> crashes I
> also noticed shutting down all of UGAIM and restarting them, made the crash
> 'stay away'.
>
> As I type I am starting and shutting down to reproduce the crash. I will
> check Mantis if
> I can add debug info , if any at all.
>
> My efforts till now to backtrace with gdb have been unsuccesful. There are
> no debugging symbols for opensim,
> or better, I do not know how to create/obtain them. Tried to hook gdb to the
> opensim' pid-id, but that stalls the running
> opensim instance completely.
>
> Maybe I should reinstall Mono and catch the warnings of the types of
> mini-trampolines.cs .. :S
>
> ----- Original Message -----
> From: "Mic Bowman"
> To: [hidden email]
> Subject: Re: [Opensim-users] Ubuntu and magic mini-trampolines (crash
> problem)
> Date: Tue, 28 Apr 2009 08:16:10 -0700
>
>
> in general we see crashes, not freezes. the apparent freeze is usually
> caused by the gdb process that gets started when the crash occurs
> (kill the gdb process and the simulator crashes "gracefully").
>
> given that the problem seems to happen when log4net attempts to get a
> logger associated with a particular script class, my guess is that one
> of a couple problems is happening... 1) mono is somehow messing up the
> class that is passed in (there are nulls in the argument stack that
> look suspicious), 2) log4net isn't as thread-safe as it claims (though
> the routine that creates the wrapper object looks fine at first
> glance), 3) somehow mono is screwing up the assembly binding when
> log4net creates the wrapper. I've looked at the mono code that is
> throwing the exception... but it wasn't very helpful without a LOT
> more investigation.
>
> at this point, i'm building a custom log4net dll with some additional
> debugging in it. which, given that this certainly appears to be a
> timing issue, will almost certainly hide the problem. :-(
>
> --mic
>
>
> On Tue, Apr 28, 2009 at 5:04 AM, Dr Scofield
> wrote:
>> Mic Bowman wrote:
>>> we've seen the problem with mono_threads_per_cpu set across a range of
>>> values (i think we've tried a number of values from 100 to 1000).
>>> there doesn't appear to be any correlation.
>>
>> ok. we had freezes that got cured by increasing MONO_THREADS_PER_CPU,
>> hence
>> my
>> asking...
>>
>> a real deadlock is nasty... :-( sigh.
>>
>>        DrS/dirk
>>>
>>> --mic
>>>
>>>
>>> On Mon, Apr 27, 2009 at 10:38 PM, dr scofield
>>> wrote:
>>>> Justin Clark-Casey wrote:
>>>>
>>>> Mic Bowman wrote:
>>>>
>>>>
>>>> I have the same freeze at times. In my case there's a gdb process
>>>> running that I can kill off to terminate the simulator.
>>>>
>>>>
>>>>
>>>> I presume there's no revealing deadlock information in the thread dump
>>>> (perhaps that's too much to hope for :) ?
>>>>
>>>>
>>>> what is your value of the MONO_THREADS_PER_CPU environment variable?
>>>>
>>>> --
>>>> dr dirk husemann ---- math & computer science ---- ibm zurich research
>>>> lab
>>>> RL: [hidden email] - +41 44 724 8573 -
>>>> http://www.zurich.ibm.com/~hud/
>>>> SL: [hidden email] ---------------------
>>>> http://xyzzyxyzzy.net/
>>>>
>>>> _______________________________________________
>>>> Opensim-users mailing list
>>>> [hidden email]
>>>> https://lists.berlios.de/mailman/listinfo/opensim-users
>>>>
>>>>
>>> _______________________________________________
>>> Opensim-users mailing list
>>> [hidden email]
>>> https://lists.berlios.de/mailman/listinfo/opensim-users
>>>
>>
>>
>> --
>> dr dirk husemann ---- virtual worlds research ---- ibm zurich research lab
>> SL: dr scofield ---- [hidden email] ---- http://xyzzyxyzzy.net/
>> RL: [hidden email] - +41 44 724 8573 - http://www.zurich.ibm.com/~hud/
>> _______________________________________________
>> Opensim-users mailing list
>> [hidden email]
>> https://lists.berlios.de/mailman/listinfo/opensim-users
>>
> _______________________________________________
> Opensim-users mailing list
> [hidden email]
> https://lists.berlios.de/mailman/listinfo/opensim-users
>
>
> __________
> WiLLuMPJuH
>
> --
> It's News. It's Reviews. It's Interviews. It's Free. What Are You Waiting
> For?
> www.movieline.com!
> _______________________________________________
> Opensim-users mailing list
> [hidden email]
> https://lists.berlios.de/mailman/listinfo/opensim-users
>
>
_______________________________________________
Opensim-users mailing list
[hidden email]
https://lists.berlios.de/mailman/listinfo/opensim-users