X-Recipient: archive-cygwin@delorie.com X-Spam-Check-By: sourceware.org Message-ID: <4783C381.3020800@huarp.harvard.edu> Date: Tue, 08 Jan 2008 13:40:01 -0500 From: Norton Allen User-Agent: Thunderbird 2.0.0.9 (Windows/20071031) MIME-Version: 1.0 To: Mr Webber , cygwin@cygwin.com Subject: Re: Does clock() work? References: <4783B96D.9060709@huarp.harvard.edu> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass (ent.arp.harvard.edu: 10.0.0.122 is authenticated by a trusted mechanism) X-IsSubscribed: yes Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm List-Id: 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 Mr Webber wrote: > CLOCKS_PER_SEC is a machine dependent macro, but not so machine dependent to > recognize that my 32-bit windows box has dual processors. Not useful for > benchmarking, is it. > It's not quite clear to me why multiple processors would affect the interpretation of CLOCKS_PER_SEC, or why such a simple model would not work in a single-threaded app for basic benchmarking. I'm not talking about a utility to launch commercial apps (which might be multithreaded, etc.), just: * record the current time * do something single-threaded * record the current time and calculate elapsed time > clock is not the way to go. It is a crude estimation of processor time. On > regular UNIX times(2) is the function to use -- cygwin does not seem to have > it. > Any other suggestions for timing resolution better than one second on cygwin? -Norton -- 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/