Further to my first answer, I think you could also visit WeakArray  
and inspect the class var FinalizationDependents.
Because of changes in when weak objects are collected, ie fixing a  
bug about when collection was actually done, we now are more likely  
to perform a finalization pass on each
incremental GC pass. If for example you find you have a WeakArray or  
subclass with say 60,000 entries in the valueDictionary you will find  
the logic actually scans each entry looking to do the finalization  
task. Iterating over 60K members every GC event does take some time,  
ie lots...

You can also check this issue by running a Vm at 3.8.6b3 or earlier  
against the image and see if you get the same behaviour since that  
version of the VM does not have the changes to how weak array  
processing is signaled.

On 26-Dec-05, at 11:42 PM, Yar Hwee Boon wrote:

> I've just started a fresh Squeak 3.8-6665 running with Mac OS X VM  
> 3.8.9beta7. I've loaded some web development stuff including  
> Seaside, Magma. Morphic response seems horribly slow compared to  
> 3.7. CPU util reads 90-100% when dragging a workspace for eg. and  
> it takes a few seconds to actually see it move. Does anyone know  
> what could be wrong or what diagnostics I can do? I'm on a 1.2 GHz  
> iBook with enough RAM, if it matters at all. Thanks!
>
> --
> Hwee Boon
> http://motionobj.com/blog/
> MotionObj
> (65) 6764-9774
>
>

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John M. McIntosh <johnmci at smalltalkconsulting.com> 1-800-477-2659
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
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