Hi all, Thanks for your comment.
@Nigel Galloway : I've done some test with and without Hypertheading and the differences are very little. I do have better performance with Hypertheading. The i7 CPU only has 2 cores. @Andrew: I think the FPU control word might be the problem. I'm running GLPK thought a JVM. I've compare the console output between glpsol.exe and a call to glp_intopt() for the same problem on the same compute running Windows 7 64bits --- the results are different. See attachments. When run from Java, it take more time. Up to 120sec. When from from glpsol.exe, it take only 4 sec. The problem is available on my dropbox : https://www.dropbox.com/sh/ja2myngas5lorow/qS2reVAFcl/assignment20120203-mip-6 Patrik Dufresne On Tue, Feb 5, 2013 at 9:14 AM, Jeffrey Kantor <[email protected]> wrote: > I know very little about hyperthreading, it's not clear that > hyperthreading limits performance of a single threaded app to one-half of a > core's performance. According to the various gamer benchmarks, > hyperthreading introduces some minor overhead on single threaded apps, but > it's not 50% penalty (unless, of course, you have a lot of other > computations going on at the same time). > > Here's a link to benchmarks for single threaded apps > http://www.cpubenchmark.net/singleThread.html. What's interesting is > that i5's, and even the lowly i3 with a high clock, can outbenchmarks some > i7 models. I wonder if this benchmark for single-threaded apps might be a > reasonable predictor of glpk performance. > > Perhaps someone with more expertise could weigh in on this. > > Jeff > > > On Tue, Feb 5, 2013 at 7:19 AM, Nigel Galloway < > [email protected]> wrote: > >> ** >> The results may consistent: >> >> Core i7 is a quad core processor with HyperThreading, so on Windows XP it >> will appear as 8 processors each running at 1.6 Ghz. GLPK can only use one >> of these processors so only 12.5% of max. >> >> Core i5 is dual core with HyperThreading. HyperThreading helps Windows' >> threading model but does nothing for Linux. You may find that your Linux >> has turned it off. So the i5 looks like 2 porcessors each running at 2.6 >> Ghz. GLPK can use 50% of this configuration. >> >> You may be able to turn off the HyperThreading on the i7 by changing your >> BIOS settings. GLPK will then be able to use 25% of max. >> >> -- >> Nigel Galloway >> [email protected] >> >> >> On Fri, Feb 1, 2013, at 08:15 AM, Reginald Beardsley wrote: >> >> Looking at the descriptions I think you're thrashing. Add more memory to >> system 1, unless of course there's a typo and that should read "32GiB" >> instead of "3GiB" >> >> --- On *Fri, 2/1/13, Patrik Dufresne <[email protected]>* wrote: >> >> >> From: Patrik Dufresne <[email protected]> >> Subject: Re: [Help-glpk] Performance decrease with more powerful computer >> To: "Reginald Beardsley" <[email protected]> >> Cc: "glpk" <[email protected]> >> Date: Friday, February 1, 2013, 9:49 AM >> >> Hi Reginald, >> >> Here are the hardware specs i'm comparing. >> >> System 1 >> Windows XP SP2 >> Intel Core i5 650 @ 3.20GHz 4 MB Cache3GiB DDR3 1066/1333CPU mark >> (according to cpubenchmark.net) : 3154 >> Total computation time : 331 sec >> >> System 2 >> Windows XP SP2, Windows 7 64bits, Debian 64bits >> Core i7 CPU M 620 @ 2.67GHz 4M Cache4GiB DDR3 1066CPU mark (according to >> cpubenchmark.net) : 2718 >> Total computation time : 114 secs >> >> System 3 >> Windows XP SP2, Debian 64bits >> *Core 2 Duo CPU E6550 @ 2.33GHz **4 MB** Cache L2*4GiB DDR2 800CPU mark >> (according to cpubenchmark.net) : 1493 >> Total computation time : 172 secs >> >> I didn't run the benchmark on the computer it self, but the different >> between the number is big enough to expect better performance from System >> no 1 then System no 3. The total computation time of the problem on >> different platform for the same computer are almost identical. (less then >> 0.5 sec different). It's safe to assume the platform doesn't have any >> impact on the performance. >> >> I'm using GLPK 4.47 on every platform. On Linux, I did compile it from >> source with default flags. For Windows, I pick the pre-compiled version >> provided by winglpk project. >> >> To solve the problem, I need to run GLPK multiple time sequentially. I >> may provide dump of every instance of the problem. >> >> Patrik Dufresne >> >> On Fri, Feb 1, 2013 at 10:23 AM, Reginald Beardsley >> <[email protected]>wrote: >> >> Could you provide a few details? >> >> System configurations you're comparing? GLPK version? Compile time >> options specified? >> >> There are a huge number of possibilities. Why do you think the computer >> is "more powerful"? >> >> Reg >> >> >> >> --- On *Fri, 2/1/13, Patrik Dufresne <[email protected]>* wrote: >> >> >> From: Patrik Dufresne <[email protected]> >> Subject: [Help-glpk] Performance decrease with more powerful computer >> To: "GLPK help" <[email protected]> >> Date: Friday, February 1, 2013, 8:56 AM >> >> >> Hi, >> >> I'm using GLPK in one project and the time taken to compute is longer on >> a more powerful computer. Does it make any sense to you ? >> >> I don't have any clues about how to debug it. I would really appreciate >> tips to diagnose the problem. >> >> Patrik Dufresne >> -----Inline Attachment Follows----- >> >> _______________________________________________ >> Help-glpk mailing list >> [email protected] <http://mc/[email protected]> >> https://lists.gnu.org/mailman/listinfo/help-glpk >> >> >> _______________________________________________ >> Help-glpk mailing list >> [email protected] >> https://lists.gnu.org/mailman/listinfo/help-glpk >> >> *_______________________________________________* >> Help-glpk mailing list >> [email protected] >> https://lists.gnu.org/mailman/listinfo/help-glpk >> >> -- http://www.fastmail.fm - A fast, anti-spam email service. >> >> >> _______________________________________________ >> Help-glpk mailing list >> [email protected] >> https://lists.gnu.org/mailman/listinfo/help-glpk >> >> > > _______________________________________________ > Help-glpk mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/help-glpk > >
glpsol-win7-x86_64.log
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glp_intopt
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