[ruby-core:63591] [ruby-trunk - Bug #10015] [Open] Performance regression in Dir#[]

[ruby-core:63591] [ruby-trunk - Bug #10015] [Open] Performance regression in Dir#[]

[tenderlove]

Issue #10015 has been reported by Aaron Patterson.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015

* Author: Aaron Patterson
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:63599] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[nobu]

Issue #10015 has been updated by Nobuyoshi Nakada.

Description updated

Yes.
Or use case-sensitive platforms.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-47654

* Author: Aaron Patterson
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:63606] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[tenderlove]

Issue #10015 has been updated by Aaron Patterson.


@nobu this change causes a significant increase in Rails boot time on my system.

My application pays a 120ms price for this change.  @hsbt will pay 520ms:

  http://twitter.com/hsbt/status/486378979138367488

Is there a way we can keep the performance on case-insensitive file systems?  If there really is no work-around, then we need to make some changes in RubyGems, bundler, minitest, and Rails before trunk is released because many people will complain about slow boot times. :(

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-47662

* Author: Aaron Patterson
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:63610] Re: [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[Eric Wong]

Btw, you're already paying significant costs for a case-insensitive FS
(not just Ruby, but things like git, too).

[ruby-core:63607] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[nobu]

Issue #10015 has been updated by Nobuyoshi Nakada.


It might affect to unintended parts.
I'll check the bottleneck.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-47663

* Author: Aaron Patterson
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:63608] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[tenderlove]

Issue #10015 has been updated by Aaron Patterson.


Thanks nobu, I really appreciate it!  If it can't be fixed, I have ideas for avoiding the calls to Dir#[], but it will take time to get merged and released.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-47664

* Author: Aaron Patterson
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:63611] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[normalperson]

Issue #10015 has been updated by Eric Wong.


 Btw, you're already paying significant costs for a case-insensitive FS
 (not just Ruby, but things like git, too).

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-47666

* Author: Aaron Patterson
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:67102] [ruby-trunk - Bug #10015] [Closed] Performance regression in Dir#[]

[nobu]

Issue #10015 has been updated by Nobuyoshi Nakada.

Status changed from Open to Closed
% Done changed from 0 to 100

Applied in changeset r48973.

----------
ChangeLog: fix ref of r48972.  [Bug #10015]

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-50614

* Author: Aaron Patterson
* Status: Closed
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:67104] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[nagachika00]

Issue #10015 has been updated by Tomoyuki Chikanaga.


note: r48975 was reverted at r48976.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-50615

* Author: Aaron Patterson
* Status: Closed
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:67116] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[matthew]

Issue #10015 has been updated by Matthew Draper.


I don't know what I'm talking about, but this seems like it could use `fcntl(2)` + `F_GETPATH`, or `getattrlist(2)` + `ATTR_CMN_NAME`.. or something along those lines -- we shouldn't need the loop+fnmatch at all, should we?

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-50621

* Author: Aaron Patterson
* Status: Closed
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:67119] [ruby-trunk - Bug #10015] Performance regression in Dir#[]

[nobu]

Issue #10015 has been updated by Nobuyoshi Nakada.


Thanks, that's it.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-50622

* Author: Aaron Patterson
* Status: Closed
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:68660] [Ruby trunk - Bug #10015] Performance regression in Dir#[]

[adrien.siami]

Issue #10015 has been updated by Adrien Siami.


I've noticed a significant slowdown of a rails app when using ruby 2.2.1 rather than 2.1.5.

A slow page was running in 16 seconds with 2.2.1 where it was running in less than 3 seconds with 2.1.5

I tested this very simple benchmark :

~~~
require 'benchmark'

puts Benchmark.realtime {
  800000.times do
    Dir['/tmp']
  end
}
~~~

it runs in 3.1289695860032225 secs with 2.2.1 and 2.403 secs with 2.1.5

Is this issue still present ?

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-51953

* Author: Aaron Patterson
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:68665] [Ruby trunk - Bug #10015] [Feedback] Performance regression in Dir#[]

[nobu]

Issue #10015 has been updated by Nobuyoshi Nakada.

Status changed from Closed to Feedback

Adrien Siami wrote:
> A slow page was running in 16 seconds with 2.2.1 where it was running in less than 3 seconds with 2.1.5
> it runs in 3.1289695860032225 secs with 2.2.1 and 2.403 secs with 2.1.5

What's your platform and filesystem?
As the former seems pretty bigger than the later, they may be caused by different reasons.

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-51958

* Author: Aaron Patterson
* Status: Feedback
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:68684] [Ruby trunk - Bug #10015] Performance regression in Dir#[]

[adrien.siami]

Issue #10015 has been updated by Adrien Siami.


Mac OS X Yosemite with the standard filesystem, I believe HFS+ Insensitive

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-51972

* Author: Aaron Patterson
* Status: Feedback
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:69492] [Ruby trunk - Bug #10015] Performance regression in Dir#[]

[karklinsh]

Issue #10015 has been updated by Magnuss Karklins.


Experiencing similar results with Adrien's benchmark:
With **ruby-2.2.2**: 2.9347980790189467
WIth **ruby-2.1.5**: 1.848318

OS X Yosemite 10.10.3, Journaled HFS+ file system.


----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-52795

* Author: Aaron Patterson
* Status: Feedback
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:69832] [Ruby trunk - Bug #10015] Performance regression in Dir#[]

[daniel]

Issue #10015 has been updated by Daniel Rikowski.


I ran Adrien's benchmark on Windows:

Besides showing a similar performance regression it looks like Dir[] is dramatically slower on Windows:

ruby-2.2.2p95: 161.4
ruby-2.1.6p336: 31.8

(Windows 8.1, SSD, NTFS)

I guess that is because of the GetFileAttributes vs. stat performance difference.

Using Process Monitor I also noticed that in 2.2.2 the (expensive) GetFileAttributesEx function is performed exactly twice as often as in 2.1.6, so part of the problems seems to be repeated (unnecessary?) calls to GetFileAttributes / stat.
(Judging from runtime behaviour only)

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-53230

* Author: Aaron Patterson
* Status: Feedback
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/

[ruby-core:74832] [Ruby trunk Bug#10015] Performance regression in Dir#[]

[layon1993]

Issue #10015 has been updated by Layon Ferreira.

ruby -v changed from ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0] to ruby 2.3.0 [x86_64-darwin13.0]
Backport changed from 2.0.0: UNKNOWN, 2.1: UNKNOWN to 2.0.0: UNKNOWN, 2.3: UNKNOWN

The problem seems to persist Mac OS X, although is better on 2.3.0, is still a lot slower than 2.1.x.
I have run the benchmark 

    require "benchmark"
    time = []
    5.times do
      result = Benchmark.realtime { 800000.times do Dir['/tmp'] end }
      puts result
      time << result
    end
    average = time.inject{ |sum, el| sum + el }.to_f / time.size    

    puts "average of: #{average}"

On this machine:

```
ProductName:	Mac OS X
ProductVersion:	10.11.4
BuildVersion:	15E65

File System Personality:  Case-sensitive Journaled HFS+
Type (Bundle):            hfs
Name (User Visible):      Mac OS Extended (Case-sensitive, Journaled)
Journal:                  Journal size 40960 KB at offset 0xe8e000
Owners:                   Enabled

```

On the all releases after 2.1.7 and got this results:

```
=====================================================
2.1.7: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.1.7
2.86774
3.012784
2.867388
2.873973
3.127474
average of: 2.9498717999999995
=====================================================
2.1.8: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.1.8
3.095918
2.981513
2.998208
3.142286
3.048603
average of: 3.0533056000000003
=====================================================
2.1.9: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.1.9
3.022291
2.983054
2.931454
2.944659
3.051114
average of: 2.9865144
=====================================================
2.2.0: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.2.0
4.985971766000148
5.047520838999844
5.066739754000082
5.005606599001112
5.0079711159996805
average of: 5.022762014800174
=====================================================
2.2.1: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.2.1
5.0500176069999725
5.031266175999917
5.011832148000394
5.043594308999673
5.0333263849988725
average of: 5.034007324999766
=====================================================
2.2.2: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.2.2
4.983856856000784
4.975439867999739
5.112457198998527
4.985339404000115
4.961809472000823
average of: 5.003780559799997
=====================================================
2.2.3: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.2.3
4.832416973000363
4.970395954000196
5.007825999999113
4.891315167000357
4.913950877999014
average of: 4.923180994399809
=====================================================
2.2.4: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.2.4
5.083285558999705
5.07147571600035
5.153286901999309
5.110161799999332
5.192000732999077
average of: 5.122042141999555
=====================================================
2.3.0: benchmarking
=====================================================
Using /Users/admin/.rvm/gems/ruby-2.3.0
3.785227087999374
3.9434133479990123
4.052104171998508
3.844644614999197
3.88892919600039
average of: 3.9028636837992963
```

----------------------------------------
Bug #10015: Performance regression in Dir#[]
https://bugs.ruby-lang.org/issues/10015#change-57959

* Author: Aaron Patterson
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0 [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.3: UNKNOWN
----------------------------------------
r44802 seems to have introduced a performance regression in Dir#[].

Here is the test program:

~~~ruby
require 'benchmark'

puts Benchmark.realtime {
  glob = "minitest/*_plugin.rb{,.rb,.bundle}"
  $LOAD_PATH.map { |load_path|
    Dir["#{File.expand_path glob, load_path}"]
  }.flatten.select { |file| File.file? file.untaint }
}
~~~

Here is the test time for me:

~~~
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44801) [x86_64-darwin13.0]
0.000341
$ ruby -v test.rb
ruby 2.2.0dev (2014-02-04 trunk 44802) [x86_64-darwin13.0]
0.009333
~~~

r44801 seems much faster than r44802.



-- 
https://bugs.ruby-lang.org/