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From:	"Dave Korn" <dave DOT korn AT artimi DOT com>
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Subject:	RE: Perl with SerialPort
Date:	Fri, 15 Feb 2008 00:06:08 -0000
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On 14 February 2008 22:52, Brian Ford wrote:

> On Wed, 13 Feb 2008, Dave Korn wrote:

>>   That diff is absolutely reliably consistently 2140 for me.  I'd
>> speculate that maybe the cygwin signal emulation requires a context
>> switch or two, to or away from the signal processing thread, and so
>> we're seeing an extra quantum or two of constant overhead for systematic
>> reasons.
> 
> Yep, two.  The minimum quantum on NT based OSes is 1024.  See this
> thread for support of your hypothesis:
> 
> http://cygwin.com/ml/cygwin-developers/2007-10/msg00040.html


  Ahh, I remember that.


  Hmm.  I wonder if it would ever be possible to avoid context switches by
doing signal processing in-thread.  It needn't necessarily matter /which/
thread "is" the signal thread as long as there's only one at a time....

    cheers,
      DaveK
-- 
Can't think of a witty .sigline today....


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