From: Robert Klemme <shortcutter@...>
Date: 2007-04-27T18:10:07+09:00
Subject: Re: 10 millisecond delay/callback

On 27.04.2007 00:08, Phrogz wrote:
> On Apr 26, 2:06 pm, khai...@enigo.com wrote:
>> On Fri, 27 Apr 2007, Earle Clubb wrote:
>>> I need to perform a task every 10ms.  I've been using
>>> kernel.sleep(0.01), but sleep seems to be slow and erratic at sub-second
>>> resolutions.  Here's a test I ran along with the results:
> [snip]
>> Try select()
> [snip]
> 
> No such glory on Windows:
> 
> irb(main):001:0> 0.upto(25) do
> irb(main):002:1* select(nil,nil,nil,0.01)
> irb(main):003:1> puts Time.now.usec/1000
> irb(main):004:1> end
> 619
> 634
> 650
> 650
> 666
> 681
> 681
> 697
> 712
> 712
> [snip]
> => 0
> irb(main):005:0>
> 
> C:\Documents and Settings\gavin.kistner>ruby -v
> ruby 1.8.5 (2006-08-25) [i386-mswin32]

This doesn't look too bad to me:

11:05:29 [~]: ruby -v
ruby 1.8.5 (2006-12-25 patchlevel 12) [i386-cygwin]
11:05:55 [~]: ruby -r enumerator <<SCRIPT
 > a = []
 > 20.times do
 > sleep 0.01
 > a << Time.now.usec / 1000.0
 > end
 > a.each_cons(2) {|x,y| puts y-x}
 > SCRIPT
11.0
11.0
10.0
11.0
11.0
11.0
10.0
11.0
11.0
11.0
10.0
11.0
11.0
11.0
10.0
11.0
11.0
11.0
10.0
11:07:04 [~]:

Kind regards

	robert