[Mulgara-general] 'Lost phase token' messages

[Andrae Muys]

On 14/11/2006, at 3:44 PM, Life is hard, and then you die wrote:
> we're seeing a fair number 'Lost phase token' messages in the logs.
> For example, after about 80 updates and 900 queries there were over
> 1100 lost-phase-token messages in the log. If I up the JVM's memory
> to 500MB it goes down to about 800. (there are only a few hundred
> statements in about 10 models in this test)
>
> Looking briefly at the code these seem mostly harmless, i.e soft
> references having been cleared. But I'm just wondering if this is
> something everybody else is seeing, or if this is indicative of some
> problem.

mmmm, it's indicative of a tuples (intermediate result) not being  
closed somewhere and leaking through to the finalizer.  It isn't  
going to cause any real trouble as the message is being printed as  
the tuples is being reclaimed by the gc.  OTOH it does mean that  
mulgara is temporarily leaking memory (and worse, possibly file  
handles).  I'm not really surprised, this is a easy mistake to make.   
When Tucana was still around, one of us would generally spend a week  
chasing down the 'lost phase tokens' just before a release.  Without  
fulltime engineers on staff, that little piece of housekeeping has  
been neglected of late.

Anyone out there interested in getting started with Mulgara  
internals?  This would be an excellent janitorial task that would  
familiarise you with the code without really requiring you to  
understand the code up front.

Andrae

-- 
Andrae Muys
andrae at netymon.com
Principal Mulgara Consultant
Netymon Pty Ltd