Deadlocking in Camel on Linux, ok on Windows

[David Godfrey <da...@gmail.com>]

I am using Camel within a web-application running on WebSphere
Application Server v7.


I am using a Camel Timer with a 1 second poll cycle. Originally I was
using Camel 2.9.1, upgraded to 2.9.6 to see if that would make any
difference.

Observed behaviour is that when run on Windows, all works perfectly
well. When running the same code on a Linux platform, I get a deadlock
in DefaultCamelContextImpl, as follows:

[22/04/13 13:56:32:586 EEST] 0000001e ThreadMonitor W   WSVR0605W:
Thread "Default : 5" (0000001b) has been active for 661957
milliseconds and may be hung.  There is/are 1 thread(s) in total in
the server that may be hung.
    at org.apache.camel.impl.DefaultCamelContext.resolveLanguage(DefaultCamelContext.java:962)

Before I post any more detail information, code examples, etc...is
this a known problem? I searched as much as I could but couldn't find
more information.

I also tweaked the config of WebSphere on the linux platform, for
example, allowing unlimited thread pool sizes to see if that made any
difference but it does not appear to do so.

many thanks!

Re: Deadlocking in Camel on Linux, ok on Windows

[Christian Müller <ch...@gmail.com>]

Hi David!

It's not a known issue. I had a short look into the code and the it happens
at the following line:
public Language resolveLanguage(String language) {
    Language answer;
    synchronized (languages) { // <- line 962
        answer = languages.get(language);

        // check if the language is singleton, if so return the shared
instance
        if (answer instanceof IsSingleton) {
            boolean singleton = ((IsSingleton) answer).isSingleton();
            if (singleton) {
                return answer;
            }
        }

        // language not known or not singleton, then use resolver
        answer = getLanguageResolver().resolveLanguage(language, this);
        if (answer != null) {
            languages.put(language, answer);
        }
    }
}

Can you raise a JIRA and attach a thread dump?

Best,
Christian


On Mon, Apr 22, 2013 at 2:28 PM, David Godfrey <da...@gmail.com> wrote:

> I am using Camel within a web-application running on WebSphere
> Application Server v7.
>
>
> I am using a Camel Timer with a 1 second poll cycle. Originally I was
> using Camel 2.9.1, upgraded to 2.9.6 to see if that would make any
> difference.
>
> Observed behaviour is that when run on Windows, all works perfectly
> well. When running the same code on a Linux platform, I get a deadlock
> in DefaultCamelContextImpl, as follows:
>
> [22/04/13 13:56:32:586 EEST] 0000001e ThreadMonitor W   WSVR0605W:
> Thread "Default : 5" (0000001b) has been active for 661957
> milliseconds and may be hung.  There is/are 1 thread(s) in total in
> the server that may be hung.
>     at
> org.apache.camel.impl.DefaultCamelContext.resolveLanguage(DefaultCamelContext.java:962)
>
> Before I post any more detail information, code examples, etc...is
> this a known problem? I searched as much as I could but couldn't find
> more information.
>
> I also tweaked the config of WebSphere on the linux platform, for
> example, allowing unlimited thread pool sizes to see if that made any
> difference but it does not appear to do so.
>
> many thanks!
>