[wildfly-dev] Gathering diagnostic data

[David M. Lloyd]

On 02/25/2014 09:26 PM, James Livingston wrote:
> Hi,
>
> I do support for JBoss at RH, especially lower level components like the
> JVM and core server, and I've come to realise that we don't have
> particularly good mechanisms for gathering diagnostic data. Obviously
> there is logging, but for a number of problems it isn't enough. There is
> also the JDR subsystem, but that has the serious limitation that the
> server instance(s) have to be working correctly to use it.
>
>
> One piece of data that I think can be useful for a common set of
> problems are thread dumps. For standalone instances Oracle/OpenJDK's
> 'jstack' tool is useful, but for domain mode you need to manually go to
> each machine and find the correct process ID to use it. Something that
> could potentially be useful is to be able to tell Host Controllers to
> take a thread dump from the servers it manages (or all of them), using
> the same Attach/SA APIs as jstack.
>
> A feature to allow HC-based extensions as mentioned in the thread about
> the RHQ agent could be useful for implementing this too. Right now, I
> believe it would need to be added to the HC code directly.
>
>
> Is this something that might be possible or a good idea to do? I have
> some ideas about other things that may be useful, like per-thread CPU
> usage which RH support currently uses a pile of shell scripts for, but
> starting with one thing may be simpler.

I believe that the management model that is already defined for host 
controllers' views of their servers could easily accommodate this kind 
of thing.  I don't think it'd have to be an extension - in fact, it 
probably should not be in this case.


-- 
- DML