X-Recipient: archive-cygwin AT delorie DOT com X-Spam-Check-By: sourceware.org Date: Fri, 4 Jun 2010 00:58:07 -0400 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: Re: Cygwin Performance and stat() Message-ID: <20100604045807.GC12167@ednor.casa.cgf.cx> Reply-To: cygwin AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com References: <4C03D6C5 DOT 4050004 AT x-ray DOT at> <80373222dd5d43b134a5ede7036e7674 DOT squirrel AT www DOT webmail DOT wingert DOT org> <20100602080626 DOT GV16885 AT calimero DOT vinschen DOT de> <383c8b44a088dad09a0b77d3299feda7 DOT squirrel AT www DOT webmail DOT wingert DOT org> <20100602174848 DOT GA14172 AT ednor DOT casa DOT cgf DOT cx> <20100603235944 DOT GA12167 AT ednor DOT casa DOT cgf DOT cx> <20100604024422 DOT GB12167 AT ednor DOT casa DOT cgf DOT cx> <78e7b77657c0cfcd63dc22ad9679bc85 DOT squirrel AT www DOT webmail DOT wingert DOT org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <78e7b77657c0cfcd63dc22ad9679bc85.squirrel@www.webmail.wingert.org> User-Agent: Mutt/1.5.20 (2009-06-14) Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: 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 On Thu, Jun 03, 2010 at 07:57:31PM -0700, Christopher Wingert wrote: >>On Thu, Jun 03, 2010 at 05:32:46PM -0700, Christopher Wingert wrote: >>Yeah, that's what I thought you were doing. Given that the timestamps >>don't indicate "elapsed time of function X", it's not always possible >>to figure out how long a function takes by subtracting. Subtracting >>timestamps shows the delta between one time that someone thought to put >>an strace_printf in the code and another time that someone thought to >>put an strace_printf in the code. There is no guarantee that there is >>an strace_printf at entry or exit of a function. > >Yes, except that someone instrumenting the entry/exit points was me, >and the fact that they are not actually real syscalls and no other >cygwin processes are running says the timestamps are accurate for the >purposes of debugging. Further the numbers match up with the overall >timings I did before the debugging. Ok, if you carefully added your own debugging calls then that's a different story. I don't see where you mentioned that anywhere until now but, nevertheless, if you've added your own entry/exit debugging then observation withdrawn. >>It is a shame that we weren't more standardized in our strace output so >>that kind of thing could be possible. > >Agreed (for once), the instrumentation of the syscalls and the fact that >they are sprinkled over multiple files made things very difficult to >debug. It's not terribly unusual to have syscalls in different files. In fact, it's probably unusual to have so many in one file, like we do with Cygwin. That's another historical artifact. >>However, for Cygwin, the web site says multiple times in multiple >>places that you shouldn't send private email and to use the mailing >>list. So, other projects aside that really is how we do things here. > >Understood. I'll wait with bated breath for a knowledgeable developer >to speak up. I'm glad not to contribute to your anoxia. I do qualify as a knowledgeable developer. In fact, I'm one of the two people who would approve/deny any patch. Btw, if you are considering a patch, you should check out the link on the website for what you need to do there. In a nutshell: we have a procedure similar to the FSF except that changes need to be assigned to Red Hat. cgf -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple