Hi Bryce,

	maybe if you use some #yield they have the chance to terminate before
creating new ones restoring balance?

	cheers,

Sebastian

 

> -----Mensaje original-----
> De: squeak-dev-bounces at lists.squeakfoundation.org 
> [mailto:squeak-dev-bounces at lists.squeakfoundation.org] En 
> nombre de bryce at kampjes.demon.co.uk
> Enviado el: Domingo, 27 de Abril de 2008 16:19
> Para: The general-purpose Squeak developers list
> Asunto: [squeak-dev] Re: Process bug introduced in 3.10
> 
> Andreas Raab writes:
>  > bryce at kampjes.demon.co.uk wrote:
>  > > My next attempt at formulating a version of the same bug that'll
>  > > run in a vanilla 3.10 image is:
>  > > 
>  > >    100 timesRepeat:
>  > > 	[processes := (1 to: 10) collect: [:each| 
> [[(MessageTally new spyEvery: 1 on: [(Delay forMilliseconds: 
> 500) wait]) ] repeat] fork ].
>  > > 	(Delay forSeconds: 1) wait.
>  > > 	processes do: [:each| each terminate].]
>  > 
>  > Running MessageTallies concurrently is a big, big no-no. 
> Check out class 
>  > MessageTally and in particular its (shared) class variables 
>  > ObservedProcess and Timer.
> 
> Good point, but I can reproduce the bug without using MessageTally
> or any class variables. ExuperyProfiler doesn't use class variables.
> 
> The following will reproduce it:
>    TestProfiler>>spyOn: aBlock 
> 	| myDelay millisecs timer |
> 	millisecs := 1.
> 	(aBlock isMemberOf: BlockContext) ifFalse: 
> 	    [self error: 'spy needs a block here'].
> 	myDelay := Delay forMilliseconds: millisecs.
> 	timer := [[true] whileTrue: 
> 					[myDelay wait].
> 			 nil] newProcess.
> 	timer priority: Processor userInterruptPriority.
> 	"activate the probe and evaluate the block"
> 	timer resume.
> 	aBlock ensure: [timer terminate].
> 	^ self
> 
>   100 timesRepeat:
> 	[processes := (1 to: 10) collect: [:each| 
> [[(TestProfiler new spyOn: [(Delay forMilliseconds: 500) 
> wait]) ] repeat] fork ].
> 	(Delay forSeconds: 1) wait.
> 	processes do: [:each| each terminate]]
> 
> TestProfiler is a new subclass of Object without any variables or
> any other methods.
> 
> I'm not convinced this is a new bug with 3.10. It feels similar to
> something I've encountered earlier. It is happening frequently in
> 3.10 but not in 3.9.
> 
> Bryce
>