X-Recipient: archive-cygwin@delorie.com X-Spam-Check-By: sourceware.org Date: Thu, 14 Feb 2008 16:52:01 -0600 From: Brian Ford Reply-To: cygwin@cygwin.com To: cygwin@cygwin.com Subject: RE: Perl with SerialPort In-Reply-To: <01d101c86e95$36d4b030$2e08a8c0@CAM.ARTIMI.COM> Message-ID: References: <15468287.post@talk.nabble.com> <01d101c86e95$36d4b030$2e08a8c0@CAM.ARTIMI.COM> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-IsSubscribed: yes Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com On Wed, 13 Feb 2008, Dave Korn wrote: > On 13 February 2008 22:59, Dave Korn wrote: > > > On 13 February 2008 22:46, Dave Korn wrote: > > > > t/01timing.............NOK 7# Failed test (t/01timing.t at line 33) > > # then: 207441765 now: 207443905 diff: 2140 > > # Looks like you failed 1 test of 7. > > t/01timing.............dubious > > 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 -- Brian Ford Lead Realtime Software Engineer VITAL - Visual Simulation Systems FlightSafety International the best safety device in any aircraft is a well-trained crew... -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/