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31 Replies Last post: Sep 25, 2009 12:48 PM by fixitchris 1 2 3 Previous Next

AV: assert from Glib + crash in a C# environment posted: Jan 2, 2009 4:42 PM

dblock

110 posts since
Dec 9, 2008

Using 1.6.2 and an ESX VM. There's something very wrong caused by a RevertToSnapshot + Disconnect call. I can reproduce this 100%. Maybe I can have symbols for vix.dll or a developer can contact me? - Thx

gvmomi.dll!036c58ba()

http://Frames below may be incorrect and/or missing, no symbols loaded for gvmomi.dll
gobject-2.0.dll!0368718c()
glib-2.0.dll!035cb0d8()
glib-2.0.dll!035cb44e()
gobject-2.0.dll!03684f7f()
gobject-2.0.dll!03687926()
vix.dll!1114a888()
vix.dll!11119135()
vix.dll!11119150()
vix.dll!111070ab()
vix.dll!111079ca()
vix.dll!1110394d()
vix.dll!1115f23f()
vix.dll!1115f950()
vix.dll!11165353()
vix.dll!11154a79()
vix.dll!111540a3()
vix.dll!11153db5()
vix.dll!11165353()
vix.dll!11165277()
vix.dll!11102678()
vix.dll!11165353()
vix.dll!11154a79()
vix.dll!1115fa93()
vix.dll!1110198d()
vix.dll!11191380()
kernel32.dll!7c80b683()

Re: AV: assert from Glib + crash in a C# environment

1. Jan 2, 2009 4:44 PM

in response to: dblock

c_shanklin

754 posts since
Dec 3, 2007

Hi, could you mention the full sequence of steps? Are you making and maintaining multiple connections by any chance?

Thanks!

Re: AV: assert from Glib + crash in a C# environment

2. Jan 2, 2009 9:32 PM

in response to: c_shanklin

dblock

110 posts since
Dec 9, 2008

I am not. It's very simple to reproduce. I wrote a repro in pure VixCOM API, no other libraries. In a loop: connect to a host, open a VM, get the root snapshot, revert to it, disconnect, force garbage collection. Attached is the repro program. The second loop crashes on my machine. If you don't force GC, obviously the crash won't happen for a while, but eventually the garbage collection will catch up with you and you'll get a random acess violation some time later.

Note that without reverting to the snapshot there's no crash.

Hope this helps.

Attachments:

VMWareCrash.zip (3.4 K)

Re: AV: assert from Glib + crash in a C# environment

3. Jan 4, 2009 10:51 PM

in response to: dblock

c_shanklin

754 posts since
Dec 3, 2007

Very helpful, thanks.

Re: AV: assert from Glib + crash in a C# environment

4. Jan 7, 2009 10:59 AM

in response to: dblock

jkovacic

11 posts since
Aug 22, 2008

Hello,

If you are not already doing so, can you please test this by calling connect and disconnect in a seperate function from the rest of the loop?

For Example:

foo(...)

{

Connect(...);

for (...) {

InnerLoop(...);

}

Disconnect(...);

}

InnerLoop(...);

{

//All the other operations

}

If this does not work, could you also place the revert to snapshot call in its own function as well? Let me know if either of these approaches solves your issue.

Re: AV: assert from Glib + crash in a C# environment

5. Jan 7, 2009 11:43 AM

in response to: dblock

zcoolmatz

3 posts since
Sep 26, 2008

I have a C# Vix Wrapper too and I got an error (attached file). I use VixCOM 1.6.2.2190 with ESX server 3.5 and Visual Studio 2005.

I have it each time that I connect and list the VM machines ( http://storage 2] .... .vmx. I'm not sure if there's another way to reproduce it... Just before I update to the 1.6.2 API, I used the VMServer 2.0 Vix API (I think it's 1.6.3(?), but I know that 1.5 work for near everything except "Capture screenshot").

If you need more info, tell me.

Thx

Attachments:

vixError1_6_2.jpg (17.6 K)

Re: AV: assert from Glib + crash in a C# environment

6. Jan 7, 2009 12:47 PM

in response to: zcoolmatz

jkovacic

11 posts since
Aug 22, 2008

Hello zcoolmatz,

Can you verify for me that your wrapper properly calls Disconnect? The error you are encountering is often associated with failing to call Disconnect.

Thank you,

Joe

Re: AV: assert from Glib + crash in a C# environment

7. Jan 8, 2009 8:35 AM

in response to: jkovacic

zcoolmatz

3 posts since
Sep 26, 2008

Hi JK,

Thx alot, I forgot to disconnect after that listing. Everything seems work now.

Thank you,

Matt

Re: AV: assert from Glib + crash in a C# environment

8. Jan 9, 2009 7:51 PM

in response to: jkovacic

dblock

110 posts since
Dec 9, 2008

None of the suggestions work around the problem: the bug on top of the loop is very real.

Re: AV: assert from Glib + crash in a C# environment

9. Jan 12, 2009 1:41 PM

in response to: dblock

jkovacic

11 posts since
Aug 22, 2008

Thank you for your response. Can you try one other thing for me? I was able to solve the issue on my own system with the solution I posted before provided I added GC.Collect(); GC.WaitForPendingFinalizers(); inside the foo loop after the call to innerLoop.

i.e

foo(...)

{
Connect(...);

for (...) {

innerLoop();

GC.Collect();
GC.WaitForPendingFinalizers();

}

Disconnect();

}

Please let me know if this solves the issue for you. Thank you.

Re: AV: assert from Glib + crash in a C# environment

10. Jan 14, 2009 9:30 AM

in response to: jkovacic

dblock

110 posts since
Dec 9, 2008

Yep, this works. Explicitly releasing the objects and garbage-collecting works around the problem. Code attached. It's still a bug, forcing GC at opportunistic places isn't going to fly for a very long time.

Attachments:

VMWareCrash.zip (4.0 K)

Re: AV: assert from Glib + crash in a C# environment

11. Jan 16, 2009 10:25 AM

in response to: dblock

jkovacic

11 posts since
Aug 22, 2008

I am glad to hear the proposed solution works for you. I agree that it is not ideal for .Net development. We are investigating the issue and hope to implement a more elegant solution for a later release of VIX. We'll be sure to consider your feedback. In the meantime, I hope this solution allows you to keep working with the VIX API and take full advantage of its potential

Re: AV: assert from Glib + crash in a C# environment

12. Feb 4, 2009 12:29 PM

in response to: dblock

fixitchris

547 posts since
Dec 8, 2006

dblock, have you found a permanent solution to this issue? I am running into a similar issue on one Linux guest with your c# wrapper. Please see my post 'vmware server 2.0 backup (win)' ;toward the end... I narrowed it down to the PowerOn method, more specifically Waitfortoolsinguest. The guest OS does have tools installed but they do not start up. I am curious why this method does not just time out and continue ... any ideas?

Re: AV: assert from Glib + crash in a C# environment

13. Feb 11, 2009 4:32 PM

in response to: fixitchris

dblock

110 posts since
Dec 9, 2008

The code I have in SVN or the latest build of VMWareTasks that GCs and nulls the right things at the right time definitely worked around the problem for me. Never tried on Linux though.