Rails Ruby on Rails → 3.1

Comments and changes to this ticket

• 

  Santiago Pastorino March 4th, 2011 @ 02:26 AM

  • Importance changed from “” to “Low”

  Hey Diego, can you benchmark that?

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  Diego Carrion March 4th, 2011 @ 03:43 AM

  Yes, no problem, will come with the results :)

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  Diego Carrion March 4th, 2011 @ 03:26 PM

  Ok, I executed 10000 times with Ruby 1.8.7 the tests, each with 3 asserts, that compares:

  Time with Time
  Time with DateTime
  Time with TimeWithZone
  DateTime with Time
  DateTime with DateTime
  DateTime with TimeWithZone

  and found that the call that is really expensive is Time#to_datetime .

  As the first patch called #to_datetime in both self and the argument in Time#<=>, the performance of comparing a Time with another Time got really bad, as two expensive unnecessary operations were being called. In the second attached patch I changed Time#<=> to only execute self#to_datetime if the argument is a datetime. With this change, the performance was improved in all cases but just a little bit, in a normal request it may be insignificant.

  Time#<=> DateTime

  before:

  47.57% 0.68% 28.62 0.41 0.00 28.21 30000 Time#<=> 285
  

       26.58   0.92    0.00    25.66   30000/30000    Time#to_datetime    290
       1.27    0.35    0.00    0.92    30000/30000    Date#compare_without_coercion   290
       0.31    0.21    0.00    0.10    30000/30000    Object#acts_like?   288
       0.05    0.05    0.00    0.00    30000/60000    Kernel#respond_to?  287
  

  after:

  47.22% 0.27% 28.49 0.17 0.00 28.33 30000 Time#<=> 280
  

       26.81   0.92    0.00    25.89   30000/30000    Time#to_datetime    281
       1.52    0.17    0.00    1.36    30000/30000    DateTime#<=>    281
  

  Time#<=> Time

  before:

  13.67% 6.31% 0.72 0.33 0.00 0.39 30000 Time#<=> 285
  

       0.30    0.21    0.00    0.10    30000/30000    Object#acts_like?   288
       0.04    0.04    0.00    0.00    30000/60000    Kernel#respond_to?  287
       0.04    0.04    0.00    0.00    30000/30000    Time#compare_without_coercion   292
  

  after:

  7.66% 4.70% 0.39 0.24 0.00 0.15 30000 Time#<=> 282
  

       0.07    0.07    0.00    0.00    30000/30000    Time#to_time    283
       0.04    0.04    0.00    0.00    30000/30000    Kernel#is_a?    283
       0.04    0.04    0.00    0.00    30000/30000    Time#compare_without_coercion   283
  

  Time#<=> TimeWithZone

  before:

  17.05% 5.52% 1.17 0.38 0.00 0.79 30000 Time#<=> 285
  

       0.39    0.26    0.00    0.13    30000/30000    ActiveSupport::TimeWithZone#respond_to? 287
       0.29    0.20    0.00    0.09    30000/30000    Object#acts_like?   288
       0.08    0.08    0.00    0.00    30000/30000    ActiveSupport::TimeWithZone#comparable_time 287
       0.04    0.04    0.00    0.00    30000/30000    Time#compare_without_coercion   292
  

  after:

  9.72% 3.77% 0.63 0.24 0.00 0.38 30000 Time#<=> 282
  

       0.19    0.11    0.00    0.08    30000/30000    ActiveSupport::TimeWithZone#to_time 283
       0.16    0.12    0.00    0.04    30000/30000    ActiveSupport::TimeWithZone#is_a?   283
       0.04    0.04    0.00    0.00    30000/30000    Time#compare_without_coercion   283
  

  • 0001-refactored-time-and-dateti.patch 3.5 KB
• 

  Santiago Pastorino March 4th, 2011 @ 06:52 PM

  • State changed from “new” to “committed”
  • Milestone set to “3.1”

  Pushed 7872cc992bac76e976334d0c20649d69aad5652e