On Mon, Jun 2, 2014 at 6:24 PM, David T. Lewis lewis@mail.msen.com wrote:

On Mon, Jun 02, 2014 at 10:14:15AM -0500, Chris Muller wrote:

...

I wouldn't be surprised if there wasn't more low-hanging fruit like this.

Well done!

Nah, if it weren't for your work no one would have noticed or been curious enough to wonder why less-than (<) could perform that poorly..

...

DateAndTime class>>#now is purposefully "slow" to assure DateAndTime now < DateAndTime now. Dave, I'm not sure whether you preserved that behavior, if not it might not be a very fair benchmark comparison..

No, I did not preserve that behavior.

Dave

...

On Mon, Jun 2, 2014 at 9:53 AM, commits@source.squeak.org wrote:

...

Chris Muller uploaded a new version of Kernel to project The Trunk: http://source.squeak.org/trunk/Kernel-cmm.855.mcz

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

Name: Kernel-cmm.855 Author: cmm Time: 2 June 2014, 9:53:24.175 am UUID: 478f3548-e587-4dd9-8962-d6ba6dbe2035 Ancestors: Kernel-eem.854

• A simple fix for an 8X performance improvement in DateAndTime>>#< as reported by LXTestDateAndTimePerformance.

=============== Diff against Kernel-eem.854 ===============

Item was changed: ----- Method: DateAndTime>>< (in category 'ansi protocol') -----

• < comparand

• < comparand "comparand conforms to protocol DateAndTime, or can be converted into something that conforms."

•   | lvalue rvalue comparandAsDateAndTime |
  

•   | lticks rticks comparandAsDateAndTime |
    comparandAsDateAndTime := comparand asDateAndTime.
    offset = comparandAsDateAndTime offset
  

•           ifTrue:
  

•                   [ lvalue := self.
  

•                   rvalue := comparandAsDateAndTime ]
  

•           ifFalse:
  

•                   [ lvalue := self asUTC.
  

•                   rvalue := comparandAsDateAndTime asUTC ].
  

•   ^ lvalue julianDayNumber < rvalue julianDayNumber or:
  

•           [ lvalue julianDayNumber > rvalue julianDayNumber
  

•                   ifTrue: [ false ]
  

•                   ifFalse:
  

•                           [ lvalue secondsSinceMidnight < rvalue secondsSinceMidnight or:
  

•                                   [ lvalue secondsSinceMidnight > rvalue secondsSinceMidnight
  

•                                           ifTrue: [ false ]
  

•                                           ifFalse: [ lvalue nanoSecond < rvalue nanoSecond ] ] ] ]!
  

•           ifTrue: [lticks := self ticks.
  

•                   rticks := comparandAsDateAndTime ticks]
  

•           ifFalse: [lticks := self asUTC ticks.
  

•                   rticks := comparandAsDateAndTime asUTC ticks].
  

•   ^ lticks first < rticks first
  

•           or: [lticks first > rticks first
  

•                           ifTrue: [false]
  

•                           ifFalse: [lticks second < rticks second
  

•                                           or: [lticks second > rticks second
  

•                                                           ifTrue: [false]
  

•                                                           ifFalse: [lticks third < rticks third]]]]
  

• !

Item was changed: ----- Method: DateAndTime>>= (in category 'ansi protocol') ----- = aDateAndTimeOrTimeStamp self == aDateAndTimeOrTimeStamp ifTrue: [ ^ true ]. ((aDateAndTimeOrTimeStamp isKindOf: self class) or: [aDateAndTimeOrTimeStamp isKindOf: DateAndTime orOf: TimeStamp]) ifFalse: [ ^ false ]. ^ self offset = aDateAndTimeOrTimeStamp offset ifTrue: [ self hasEqualTicks: aDateAndTimeOrTimeStamp ]

•           ifFalse: [ self asUTC hasEqualTicks: aDateAndTimeOrTimeStamp asUTC ]!
  

•           ifFalse: [ self asUTC ticks = aDateAndTimeOrTimeStamp asUTC ticks ]!