Poor performance on Windows

[Maher4Ever]

The FChange gem is implemented in the default Windows adapter, but it might not be the best choice. It turns out that the polling adapter is a lot faster on Windows than the FChange one (my machine is running ruby 1.9.3-p125 on Windows 7 SP 1). I tried profiling the FChange gem with ruby-prof on WIndows and I found an interesting fact: By attaching a FChange watcher to a directory, a simple touch and rm of a file takes 1.502 sec instead of 0.002, which is more than 99% slower! ( link to code and results )

In light of this discovery I think it would be reasonable to just use the poll adapter as the default one for Windows. What do you think @thibaudgg ?

[thibaudgg]

Yeah if it's really so much slower using the poll adapter now seems a good decision but it would be if that could be a temporary workaround.

@stereobooster do you have a idea about why rb-fchange is slower than polling?

[stereobooster]

I have no clue. I need to investigate it.

[Maher4Ever]

For anyone interested in helping us get more results on this performance issue, you could download a profile script which has a "how to use" file. The only thing you should have before running the script is a version of ruby installed. You could use this link to get ruby installer, then dev-kit is needed to run the profiler.

[TheDutchCoder]

@Maher4Ever I have Ruby installed, including the dev-kit, but the instructions in the Read Me file for the profiler don't work for me. 'bundle' is not working (not recognized as a command).

I installed bundler (which is not part of the RubyInstaller for Windows), but then it throws the following error:
F:\Installs\profile-fchange>bundle install
Your Gemfile has no remote sources. If you need gems that are not already on
your machine, add a line like this to your Gemfile:
source 'https://rubygems.org'
Could not find ffi-1.0.11 in any of the sources

Also, the instructions in step 1 aren't totally clear: "... and go to this directory" (I figure "this" is the dir where I extracted the profiler?)

[Maher4Ever]

@reinierk Thank you for reporting these issues with the profiling package. I'm too used to having bundler automatically installs itself with each ruby I install that I forgot it's not (yet) a part of ruby.
Anyhow, I just re-installed RubyInstaller from scratch to ensure I have a clean slate and I corrected the script to work with it. I also tried to explain every step more in the instructions.

To make it possible for everyone to help with the script, I made a repository for it. I would appreciate it if you could download the zip from the new repository and give it another try.

[TheDutchCoder]

@Maher4Ever Thanks for that, makes it easier to understand and good to point out bundler.
Install went fine after that with the new profiler zip and I will try it out and post results in the new repo.

[TheDutchCoder]

Here are my results!
http://www.x-plicit4.nl/results.zip

[TheDutchCoder]

@Maher4Ever were my results of any use for you and/or do you want me to do another (couple of) run(s)?

[Maher4Ever]

@reinierk Thank you for proving us with your result, it is very helpful and confirms that using FChange incurs a performance penalty for a core ruby method File#initialize. Without FChange, calling that method happens in almost no time, but with FChange there is a delay of 1.5 sec.

@stereobooster Have you had time to look into this issue?

[codylerum]

I did see this same behavior on 1.9.3 but works fine on ruby 1.9.2p290

[Maher4Ever]

@codylerum Can you please provide us with your results for the profiling script with more info about your system? I ran the profiling script on ruby 1.9.2p290 on Window 7 (64bit) and the results were almost identical to the results of ruby 1.9.3.

[codylerum]

@Maher4Ever I don't seem to be able to install the required "fileutils" even though I have devkit installed (verified by running gem install rdiscount --platform=ruby)

This is on 1.9.2p290

Errors on building rmagick-2.13.1

[Maher4Ever]

@codylerum FileUtils is a part of the ruby stdlib, so you don't have to install it. Did you follow the usage instructions on the repo of the profiling script?

[codylerum]

@Maher4Ever I was running from a link further up in the issue. Let me gather the results

[codylerum]

@Maher4Ever Results: https://dl.dropbox.com/u/86734110/results.zip

I'm not sure if my issue is performance based or that it just isn't picking up on file modifications in 1.9.3 where it does just fine in 1.9.2

[Elufimov]

@Maher4Ever https://dl.dropbox.com/u/13579347/results.zip
Windows 4 x64 and ruby 1.9.3p125 (2012-02-16) [i386-mingw32]

[Maher4Ever]

I just pushed the source of a new gem I called Windows Directory Monitor (WDM). It's still very experimental, but in my tests it performs faster than any comparable library on Windows. WDM still needs a lot of work, so don't expect it to be ready any time soon.

[mrbinky3000]

Greetings. I would just like to +1 the performance issue on Windows. This gem is part of Middleman and as a result, it is making Middleman unusable on Windows 7 machines. If there is anything I can do to help out, let me know.

[thibaudgg]

@mrbinky3000 have you been able to give a try to WDM gem?
@Maher4Ever have you a release date in mind?

[andrew-aladev]

I've tested @Maher4Ever 's pull request with middleman. it works perfect

@thibaudgg can you make a new release of listen? I will notify @tdreyno to make a new version of middleman too. I am sure that our windows-based designers will be happy ^___^

[Maher4Ever]

@thibaudgg I was very busy for the last couple of weeks. I'll try to update WDM docs today and then release a new version of Listen.

@andrew-aladev Great to know WDM fixed your problem :)

[thibaudgg]

@Maher4Ever no problem, take your time Maher and have a nice week-end. Thanks!

[Maher4Ever]

Listen 0.5.0 has been released :)

[thibaudgg]

@Maher4Ever Awesome!