Can I get a notification before fullGC?

John M McIntosh johnmci at
Thu Oct 12 14:08:25 UTC 2006

The VM has a counter that is incremented on each fullGC, you could  
have a periodic task that runs that pulls that vm statistic and then  
does what ever
when the fullGC counter increments.  However when or if a fullGC will  
run is always an interesting question.

On 12-Oct-06, at 3:23 AM, Yoshiki Ohshima wrote:

>   Thank you Andreas and Bert,
>> Personally, I find this behavior advantageous. The glyph cache can be
>> chosen to accommodate the working set for most use cases (I find the
>> current one too large by far but see below) and I wouldn't really  
>> want
>> to recreate the glyphs after each full GC.
>   BTW, a typical use case I was thinking is project transition.  The
> working sets can be pretty different across projects... (So, flushing
> the cache upon project transition may be a good idea.)
>   In regards to the one more mapping for different colors, I'd
> delegate the measurement by somebody else, at least for the "October
> release".
>   And, memoryHog is a bit too tight.  The purpose is rather be a
> better citizen to a relatively limited system, than avoiding critical
> situations.
>   A special array to nil-out upon fullGC would be good.  (If we have a
> flexible and dynamically modifiable VM, this approach would make more
> sense.)
> -- Yoshiki

John M. McIntosh <johnmci at>
Corporate Smalltalk Consulting Ltd.

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