Fwd: [Squeak-VMdev] Re: GC improvements

[John M M. <jo...@ma...>]

Oops wrong email address, try again to vmdev

Begin forwarded message:

> From: John M McIntosh <jo...@sm...>
> Date: January 19, 2005 12:47:00 AM PST
> To: "Andreas Raab" <and...@gm...>
> Cc: "Squeak VM Developers" <squ...@li...>, "Tim  
> Rowledge" <ti...@su...>, "Ian Piumarta"  
> <ian...@hp...>
> Subject: Re: [Squeak-VMdev] Re: GC improvements
>
>
> On Jan 19, 2005, at 12:26 AM, Andreas Raab wrote:
>
>> With this aggressive growth strategy I think we should have a (VM)  
>> parameter which controls when to run a full GC depending on how much  
>> we've grown. Having a GC tuner sit there all the time and watch  
>> things fly by doesn't look like the best solution to me.
>>
>> On the other hand it seems like in this case we probably should be  
>> following the same strategy in sufficientSpaceAfterGC:, shouldn't we?  
>> Here, we just GC and then grow and it seems that if we're okay with  
>> aggressive growths me grow here, too.
>
> Ok, do you want to move the logic to the VM, the change is after we  
> grown N MB (settable value) we then do a full GC.
>
>> If you look at them, all can be computed by other means, say:
>>
>> statMarkCount:
>>    Number of marked objects ==
>>        Number of roots + Number of survivors
>
> Actually this is the number of times around the marking loop, I don't  
> think it's same as the survivor count plus roots.
>
>
> I think these below look ok
>
>>
>> statSweepCount
>>    Number of objects in young space before GC ==
>>        Number of survivors of last GC + allocationsBetweenGC
>>
>> statMkFwdCount
>>    Number of objects for which fwdBlocks were created ==
>>        Number of survivors
>>
>> statCompMoveCount
>>    Number of chunks touched in incr. compaction ==
>>        statSweepCount
>>
>> So there really isn't any need to count them one by one (if the  
>> result of counting would be different from the above formulaes it's  
>> time to get a new CPU which gets addition right ;-)
>>
>> Cheers,
>>  - Andreas
>>
>>
> --
> ======================================================================= 
> ====
> John M. McIntosh <jo...@sm...> 1-800-477-2659
> Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
> ======================================================================= 
> ====
>
>
--
======================================================================== 
===
John M. McIntosh <jo...@sm...> 1-800-477-2659
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
======================================================================== 
===