[Topaz-dev] Mulgara Performance Woes

[Life is hard, and then you die]

On Sat, Mar 01, 2008 at 08:15:30AM -0800, Russell Uman wrote:
> Andrae Muys wrote:
> > On 01/03/2008, at 7:24 AM, Life is hard, and then you die wrote:
> >> First of all we're (currently) running this as a webapp in tomcat, and
> >> second using jmx (sorry, not jms as I wrote above) you don't need to
> >> restart - we should consider adding some jmx support to mulgara.
> > 
> > At one point we did support JMX - I'm not sure if that code is still  
> > there sitting dormant and undocumented, but it was once there.  If  
> > anyone remembers what happened to it it will be Simon Raboczi.

Thanks - I'll take a look soon.

> i believe it's still there - we've got jmanage up and running,
> connecting quite happily to mulgara - but i'm not sure what useful
> things i can do with it now that it's up...

Hold on, don't get things confused here. JMX is always available on
every single java app, provided you start it the the appropriate
options (-Dcom.sun.management.jmxremote...). There is some useful info
provided by the jvm out of the box, but that's not what we're talking
about. What we're talking about is mulgara (and log4j/other libs)
specific jmx mbeans so you can look at and set/modify mulgara (and
log4j) specific things. E.g. it might be useful to get a list of
existing sessions, see who holds the write lock, get query stats, etc,
and maybe even to be able close a session (possibly releasing the
write-lock) or change the transaction timeout. All these require one
or more mulgara-specific mbeans to be written, though it's usually
fairly simple to do.


  Cheers,

  Ronald