That is very interesting! I've looked at how Python does benchmarking and it does not use QPC:
On Windows, QueryPerformanceCounter() is not used even though it has a better resolution than GetTickCount() . It is not reliable and has too many issues. https://www.python.org/dev/peps/pep-0418/ So we could switch to use GetTickCount() instead but the drawback is that that function has abysmal resolution. Then again, XP is a very old operating system.. 2016-07-24 23:43 GMT+02:00 Alexander Ilin <ajs...@yandex.ru>: > Hello! > > It looks like adding the /usepmtimer switch to the boot.ini has fixed the > problem for that PC. At least the same test cases no longer reproduce the > error after a reboot. > > Source of inspiration: http://www.virtualdub.org/blog/pivot/entry.php?id=106 > > 24.07.2016, 21:59, "Alexander Ilin" <ajs...@yandex.ru>: >> Hello! >> >> I'm having a weird problem with the benchmark word on my WinXP SP3 32-bit >> machine, running the latest Factor from Github master. >> >> The benchmark word reports times under or about 1 second (1,000,000,000) >> for some piece of code, but the actual run time of the quotation is always >> about 5-6 seconds. >> >> For example, here's a sketch of a test session, without restarting a >> Factor instance, done in the following order. >> >> This code would show running time < 1 sec: >> >> [ do-smth ] benchmark >> >> Then this code would show the correct wall time for both the time word and >> the benchmark word: >> >> [ [ do-smth ] time ] benchmark >> >> This would show the correct timing for both words as well: >> >> [ [ do-smth ] benchmark ] time >> >> Finally, returning to this code again measures incorrectly (< 1 sec): >> >> [ do-smth ] benchmark >> >> Has anyone experienced anything like this before? >> >> Replacing [ do-smth ] with [ now do-smth now ] shows the correct time in >> all cases, and by calculating difference I can see that benchmark calculates >> incorrectly. But I can't figure out the reason. >> >> On the other hand, replacing [ do-smth ] with [ nano-count do-smth >> nano-count ] I see that benchmark is right. So, the problem is that for some >> reason nano-count returns lower time difference for the code I run, >> depending on the way I run it - with or without the "time" word. > > ---=====--- > Александр > > ------------------------------------------------------------------------------ > What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic > patterns at an interface-level. Reveals which users, apps, and protocols are > consuming the most bandwidth. Provides multi-vendor support for NetFlow, > J-Flow, sFlow and other flows. Make informed decisions using capacity planning > reports.http://sdm.link/zohodev2dev > _______________________________________________ > Factor-talk mailing list > Factor-talk@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/factor-talk -- mvh/best regards Björn Lindqvist ------------------------------------------------------------------------------ _______________________________________________ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
