Marcel Taeumel uploaded a new version of System to project The Trunk:
http://source.squeak.org/trunk/System-mt.1216.mcz

==================== Summary ====================

Name: System-mt.1216
Author: mt
Time: 18 February 2021, 9:16:17.196751 am
UUID: 70862cfd-0be1-453a-b6af-8697996913ba
Ancestors: System-mt.1215

Replaces direct access to class var with accessor to make resetting of pragma preference work.

=============== Diff against System-mt.1215 ===============

Item was changed:
  ----- Method: MessageTally class>>initialize (in category 'class initialization') -----
  initialize
  	"MessageTally initialize"
- 	"By default, show each process separately"
- 	ShowProcesses ifNil: [ShowProcesses := true].
  	Smalltalk
  		addToShutDownList: self after: Delay; "i.e. convert to relative times & stats after Delay sleeps."
  		addToStartUpList: self before: Delay "i.e. convert back to absolute stats before Delay wakes."!

Item was changed:
  ----- Method: MessageTally class>>spyOn: (in category 'spying') -----
  spyOn: aBlock
  	"Spy on aBlock, in the current process. Can include or not statistics on other processes in the report.
  	[1000 timesRepeat: [
  		100 timesRepeat: [120 factorial].
  		(Delay forMilliseconds: 10) wait
  		]] forkAt: 45 named: '45'.
  	MessageTally spyOn: [10000 timesRepeat: [1.23 printString]]
  	"
+ 	^self spyOn: aBlock reportOtherProcesses: self showProcesses!
- 	^self spyOn: aBlock reportOtherProcesses: ShowProcesses!

Item was changed:
  ----- Method: MessageTally class>>spyOnProcess:forMilliseconds: (in category 'spying') -----
  spyOnProcess: aProcess forMilliseconds: msecDuration 
  	"
  	Spy on aProcess for a certain amount of time
  	| p1 p2 |  
  	p1 := [100000 timesRepeat: [3.14159 printString. Processor yield]] newProcess.  
  	p2 := [100000 timesRepeat: [3.14159 printString. Processor yield]] newProcess.
  	p1 resume.
  	p2 resume.  
  	(Delay forMilliseconds: 100) wait.  
  	MessageTally spyOnProcess: p1 forMilliseconds: 1000
  	"
  	
  	^self 
  		spyOnProcess: aProcess
  		forMilliseconds: msecDuration
+ 		reportOtherProcesses: self showProcesses
- 		reportOtherProcesses: ShowProcesses
  !