Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Date: Sun, 27 Jun 2004 19:43:50 -0400 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: Re: higher-level IO very slow with cygwin1.dll 5.10 (due to set_flags?) Message-ID: <20040627234350.GA13744@trixie.casa.cgf.cx> Reply-To: cygwin AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com References: <20040626154504 DOT GA961349 AT hpn5170x> <20040626160554 DOT GA980221 AT hpn5170x> <20040626170940 DOT GD20063 AT trixie DOT casa DOT cgf DOT cx> <20040626174145 DOT GA1032441 AT hpn5170x> <20040627194205 DOT GA10371 AT trixie DOT casa DOT cgf DOT cx> <20040627212949 DOT GA176017 AT Worldnet> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040627212949.GA176017@Worldnet> User-Agent: Mutt/1.4.1i On Sun, Jun 27, 2004 at 05:29:50PM -0400, Pierre A. Humblet wrote: >On Sun, Jun 27, 2004 at 03:42:05PM -0400, Christopher Faylor wrote: >> On Sat, Jun 26, 2004 at 01:41:45PM -0400, Pierre A. Humblet wrote: > >> >Digging deeper, I see there is a function getc_unlocked. Using it >> >instead of getc improves the speed by a factor 5. >> >Now that I know about it, I will redefine getc to getc_unlocked when >> >porting single threaded applications. >> > >> >That issue may be a factor in the legendary slowness of Cygwin. >> >> FWIW, I added some code to this particular locking function to avoid >> doing any locks if there is only one thread. I'm generating a snapshot >> now. It will be interesting to see if it improves things. I didn't >> do any benchmarking. I just verified that it worked the way I thought >> it should by looking at strace output. > >Here it is, using a slightly modified version of Joseph's program >http://cygwin.com/ml/cygwin/2004-06/msg00877.html > >Your change makes getc work almost as fast a getc_unlocked. >This is on Win98. Yesterday's results were on WinME, where the >differences were larger. That hard drive died this morning :( Sorry to hear that. I've been going through hard disk problems myself. Thanks for verifying that the change worked. cgf -- 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/