Nicolas Cellier uploaded a new version of Chronology-Core to project The Trunk:
http://source.squeak.org/trunk/Chronology-Core-nice.44.mcz

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

Name: Chronology-Core-nice.44
Author: nice
Time: 6 May 2019, 9:25:01.091073 am
UUID: aec07289-9959-4dcf-b422-3079111e5ed3
Ancestors: Chronology-Core-nice.43

Fixup: use highResClock provided by self (Time) rather than Smalltalk (which is a dependency of AndreasSystemProfiler)

=============== Diff against Chronology-Core-nice.43 ===============

Item was changed:
  ----- Method: Time class>>estimateHighResClockTicksPerMillisecond (in category 'clock') -----
  estimateHighResClockTicksPerMillisecond
  
  	| t0 t1 t2 t3 |
  	
  	"Count the ticks ellapsed during a 10ms busy loop"
  	t0 := Time utcMicrosecondClock + 200.
  	[Time utcMicrosecondClock >= t0] whileFalse.
+ 	t1 := self highResClock.
- 	t1 := Smalltalk highResClock.
  	[Time utcMicrosecondClock >= (t0 + 10000)] whileFalse.
+ 	t1 := self highResClock - t1 * 1000 // (Time utcMicrosecondClock - t0).
- 	t1 := Smalltalk highResClock - t1 * 1000 // (Time utcMicrosecondClock - t0).
  	
  	"Count the ticks ellapsed during a 20ms busy loop"
  	t0 := Time utcMicrosecondClock + 200.
  	[Time utcMicrosecondClock >= t0] whileFalse.
+ 	t2 := self highResClock.
- 	t2 := Smalltalk highResClock.
  	[Time utcMicrosecondClock >= (t0 + 20000)] whileFalse.
+ 	t2 := self highResClock - t2 * 1000 // (Time utcMicrosecondClock - t0).
- 	t2 := Smalltalk highResClock - t2 * 1000 // (Time utcMicrosecondClock - t0).
  	
  	"Count the ticks ellapsed during a 30ms busy loop"
  	t0 := Time utcMicrosecondClock + 200.
  	[Time utcMicrosecondClock >= t0] whileFalse.
+ 	t3 := self highResClock.
- 	t3 := Smalltalk highResClock.
  	[Time utcMicrosecondClock >= (t0 + 30000)] whileFalse.
+ 	t3 := self highResClock - t3 * 1000 // (Time utcMicrosecondClock - t0).
- 	t3 := Smalltalk highResClock - t3 * 1000 // (Time utcMicrosecondClock - t0).
  	
  	"Take the median of the 3 estimates as the best"
  	^ t1 <= t2
  		ifTrue: [t2 <= t3
  				ifTrue: [t2]
  				ifFalse: [t1 <= t3
  						ifTrue: [t3]
  						ifFalse: [t1]]]
  		ifFalse: [t1 <= t3
  				ifTrue: [t1]
  				ifFalse: [t2 <= t3
  						ifTrue: [t3]
  						ifFalse: [t2]]]!