Deadlock

Asterisk Asterisk Support
1

I’ve been trying to troubleshoot * locking up on me. I was curious if someone could explain what these messages mean and if it’s something that I should be worried about or that could be causing * to be locking up on me.

I simply grepped for deadlock in my logfile.

Jan 31 16:33:46 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-b6fe,2’
Jan 31 16:33:47 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-648d,2’
Jan 31 16:33:48 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-f5ab,2’
Jan 31 16:34:02 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-f504,2’
Jan 31 16:34:14 DEBUG[7429] channel.c: Avoiding initial deadlock for 'SIP/10.0.4.2-091bb4e8’
Jan 31 16:34:21 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-e75e,2’
Jan 31 16:34:21 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-e75e,2’
Jan 31 16:34:21 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-e75e,2’
Jan 31 16:34:21 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-e75e,2’
Jan 31 16:34:29 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-759d,2’
Jan 31 16:34:32 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-0909,2’
Jan 31 16:34:35 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-adb0,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3afa,2’
Jan 31 16:37:04 WARNING[7429] channel.c: Avoided initial deadlock for ‘0x90f68b8’, 10 retries!
Jan 31 16:37:07 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-1048,2’
Jan 31 16:37:10 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-da3b,2’
Jan 31 16:37:12 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-4cc3,2’
Jan 31 16:37:15 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-315a,2’
Jan 31 16:37:17 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-3647,2’
Jan 31 16:37:21 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-e25e,2’
Jan 31 16:37:22 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-9e9b,2’
Jan 31 16:37:22 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-9e9b,2’
Jan 31 16:37:22 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-9e9b,2’
Jan 31 16:37:22 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-9e9b,2’
Jan 31 16:37:24 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-eff0,2’
Jan 31 16:37:27 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2313240@examplecontext-a8d7,2’
Jan 31 16:37:28 DEBUG[7429] channel.c: Avoiding initial deadlock for 'Local/2303240@examplecontext-a0c8,2’
Jan 31 16:37:31 DEBUG[7429] channel.c: Avoiding initial deadlock for ‘Local/2313240@examplecontext-902d,2’.

2

Next step is

http://www.voip-info.org/wiki/index.php?page=Asterisk+deadlock

How far along are you with this? Does your situation match the signs/symptoms described?

Have you tried a complete make clean and recompile?

3

Yeah, I’ve read that document and it does match those symptoms when it deadlocks. The messages above are pretty much being logged all the time and its locked up a total of 4 times in the past 5 months.

I think I’m going to try a newer version of asterisk. Right now I’m on 1.2.11 rev 40948 and I’ll likely be moving to 1.2.13 rev 47264. I noticed some deadlock fixes in the changelog between these versions.

I didn’t just pick these versions out of the sky. I’m using trixbox 1.2.2 currently (which has * 1.2.11) and am going to install trixbox 2.0 (which has * 1.2.13).

I haven’t recompiled yet, so far I’ve just been trying to determine what exactly was breaking.

My main question is: What are these messages telling me?

Is it "A deadlock almost occured, but I’m a good little * and I caught it"
Or “Hey, you got some problems bud and I saved your butt this time but I’m not sure if I can do it again”?

4

From a non-asterisk document on databases I found the following definition:

A deadlock exists whenever two or more processes,
which are vying for the same resources, reach an
impasse.

In this context, according to your debug channel.c is trying to establish a connection, but some other * process else already has an exclusive grip on essential related resources.