Jeff Roberson wrote: > On Mon, 3 Nov 2003, Eirik Oeverby wrote: > > >>Hi, >> >>Just recompiled yesterday, running sched_ule.c 1.75. It seems to have >>re-introduced the bogus mouse events I talked about earlier, after a >>period of having no problems with it. The change happened between 1.69 >>and 1.75, and there's also the occational glitch in keyboard input. > > > How unfortunate, it seems to have fixed other problems. Can you describe > the mouse problem? Is it jittery constantly or only under load? Or are > you having other problems? Have you tried reverting to SCHED_4BSD? What > window manager do you run? The problem is two parts: The mouse tends to 'lock up' for brief moments when the system is under load, in particular during heavy UI operations or when doing compile jobs and such. The second part of the problem is related, and is manifested by the mouse actually making movements I never asked it to make. It's almost as if messages passed from the mouse (PS/2 type) through the kernel are being corrupted or lost - moving the mouse slowly in one direction will suddenly make it jump half across the screen and continue. Also it will quite often produce bogus clicks and drags, i.e. I'll be moving the mouse across the screen and suddenly it grabs something and doesn't let go - as if it got a MouseRightDown event but no MouseRightRelease event (or whatever they are called in the world you are in - I'm coming from OS/2 and other obscure platforms ;). The second problem usually follows the first - it's more likely to happen when the system is under some kind of load. Heavy window repainting/updating (Mozilla Thunderbird is a prime example, but other apps can be just as guilty), compile jobs, VMWare going crazy with the CPU, heavy disk/network I/O .. Anything that places load on the system/kernel can cause this. Running with SCHED_4BSD completely solves these problems, and the bogus mouse event problems did NOT appear with sched_ule 1.69 (which is the last one I tried before 1.75). It did appear with ~1.50 and thereabouts though (as reported earlier in this thread). I'm currently running WindowMaker as window manager, but the problem also exists in Gnome and xfce4. Gnome is more likely to exhibit the problem even during low system loads, given that it's more violent UI-wise. You are right though, the later sched_ule revisions DO seem to be better in many other respects - overall performance 'feels' better (atleast in console mode). The mouse issues makes X kinda hard to use though. Btw you might be interested in knowing that the keyboard from time to time shows what I think is bogus input aswell - I have a consistently higher rate of failure when typing with sched_ule 1.75 than I had with 1.69, and it definitely feels as if keystrokes are getting lost or repeated when they shouldn't be. Not often, had two or three 'suspicious' typos while writing this message, and I am reluctant to say it's a definite kernel issue, because I'm nowhere near a perfect typist - but it is nevertheless worth noting and might even be worth looking into. Might there be a connection between this and the mouse issues? Thanks, /Eirik > > Thanks for the report. > > Cheers, > Jeff > > >>If you need me to do anything to track this down, let me know. I am, and >>have always been, running with moused, on a uniprocessor box (ThinkPad >>T21 1ghz p3). >> >>Best regards, >>/Eirik >> >>Jeff Roberson wrote: >> >>>On Fri, 31 Oct 2003, Bruno Van Den Bossche wrote: >>> >>> >>> >>>>Jeff Roberson <jroberson_at_chesapeake.net> wrote: >>>> >>>> >>>> >>>>>On Wed, 29 Oct 2003, Jeff Roberson wrote: >>>>> >>>>> >>>>> >>>>>>On Thu, 30 Oct 2003, Bruce Evans wrote: >>>>>> >>>>>> >>>>>> >>>>>>>>Test for scheduling buildworlds: >>>>>>>> >>>>>>>> cd /usr/src/usr.bin >>>>>>>> for i in obj depend all >>>>>>>> do >>>>>>>> MAKEOBJDIRPREFIX=/somewhere/obj time make -s -j16 $i >>>>>>>> done >/tmp/zqz 2>&1 >>>>>>>> >>>>>>>>(Run this with an empty /somewhere/obj. The all stage doesn't >>>>>>>>quite finish.) On an ABIT BP6 system with a 400MHz and a 366MHz >>>>>>>>CPU, with/usr (including /usr/src) nfs-mounted (with 100 Mbps >>>>>>>>ethernet and a reasonably fast server) and /somewhere/obj >>>>>>>>ufs1-mounted (on a fairly slow disk; no soft-updates), this >>>>>>>>gives the following times: >>>>>>>> >>>>>>>>SCHED_ULE-yesterday, with not so careful setup: >>>>>>>> 40.37 real 8.26 user 6.26 sys >>>>>>>> 278.90 real 59.35 user 41.32 sys >>>>>>>> 341.82 real 307.38 user 69.01 sys >>>>>>>>SCHED_ULE-today, run immediately after booting: >>>>>>>> 41.51 real 7.97 user 6.42 sys >>>>>>>> 306.64 real 59.66 user 40.68 sys >>>>>>>> 346.48 real 305.54 user 69.97 sys >>>>>>>>SCHED_4BSD-yesterday, with not so careful setup: >>>>>>>> [same as today except the depend step was 10 seconds >>>>>>>> slower (real)] >>>>>>>>SCHED_4BSD-today, run immediately after booting: >>>>>>>> 18.89 real 8.01 user 6.66 sys >>>>>>>> 128.17 real 58.33 user 43.61 sys >>>>>>>> 291.59 real 308.48 user 72.33 sys >>>>>>>>SCHED_4BSD-yesterday, with a UP kernel (running on the 366 MHz >>>>>>>>CPU) with >>>>>>>> many local changes and not so careful setup: >>>>>>>> 17.39 real 8.28 user 5.49 sys >>>>>>>> 130.51 real 60.97 user 34.63 sys >>>>>>>> 390.68 real 310.78 user 60.55 sys >>>>>>>> >>>>>>>>Summary: SCHED_ULE was more than twice as slow as SCHED_4BSD for >>>>>>>>the obj and depend stages. These stages have little >>>>>>>>parallelism. SCHED_ULE was only 19% slower for the all stage. >>>>>>>>... >>>>>>> >>>>>>>I reran this with -current (sched_ule.c 1.68, etc.). Result: no >>>>>>>significant change. However, with a UP kernel there was no >>>>>>>significant difference between the times for SCHED_ULE and >>>>>>>SCHED_4BSD. >>>>>> >>>>>>There was a significant difference on UP until last week. I'm >>>>>>working on SMP now. I have some patches but they aren't quite ready >>>>>>yet. >>>>> >>>>>I have commited my SMP fixes. I would appreciate it if you could post >>>>>update results. ULE now outperforms 4BSD in a single threaded kernel >>>>>compile and performs almost identically in a 16 way make. I still >>>>>have a few more things that I can do to improve the situation. I >>>>>would expect ULE to pull further ahead in the months to come. >>>> >>>>I recently had to complete a little piece of software in a course on >>>>parallel computing. I've put it online[1] (we only had to write the >>>>pract2.cpp file). It calculates the inverse of a Vandermonde matrix and >>>>allows you to spawn multiple slave-processes who each perform a part of >>>>the work. Everything happens in memory so >>>>I've used it lately to test the different changes you made to >>>>sched_ule.c and these last fixes do improve the performance on my dual >>>>p3 machine a lot. >>>> >>>>Here are the results of my (very limited tests) : >>>> >>>>sched4bsd >>>>--- >>>>dimension slaves time >>>>1000 1 90.925408 >>>>1000 2 58.897038 >>>> >>>>200 1 0.735962 >>>>200 2 0.676660 >>>> >>>>sched_ule 1.68 >>>>--- >>>>dimension slaves time >>>>1000 1 90.951015 >>>>1000 2 70.402845 >>>> >>>>200 1 0.743551 >>>>200 2 1.900455 >>>> >>>>sched_ule 1.70 >>>>--- >>>>dimension slaves time >>>>1000 1 90.782309 >>>>1000 2 57.207351 >>>> >>>>200 1 0.739998 >>>>200 2 0.383545 >>>> >>>> >>>>I'm not really sure if this is very relevant to you, but from the >>>>end-user point of view (me :-)) this does means something. >>>>Thanks! >>> >>> >>>I welcome the feedback, positive or negative, as it helps me improve >>>things. Thanks for the report! Could you run this again under 4bsd and >>>ULE with the following in your .cshrc: >>> >>>set time= ( 5 "%Uu %Ss %E %P %X+%Dk %I+%Oio %Fpf+%Ww %cc/%ww" ) >>> >>>And then time ./testpract 200 2, etc. This will give me a few hints about >>>what's impacting your performance. >>> >>>Thanks! >>>Jeff >>> >>> >>> >>>>[1] <http://users.pandora.be/bomberboy/mptest/final.tar.bz2> >>>>It can be used by running testpract2 with two arguments, the dimension >>>>of the matrix and the number of slaves. example './testpract2 200 2' >>>>will create a matrix with dimension 200 and 2 slaves. >>>> >>>> >>>>-- >>>>Bruno >>>> >>>>... And then there's the guy who bought 20,000 bras, cut them in half, >>>>and sold 40,000 yamalchas with chin straps.... >>>> >>> >>> >>>_______________________________________________ >>>freebsd-current_at_freebsd.org mailing list >>>http://lists.freebsd.org/mailman/listinfo/freebsd-current >>>To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org" >> >> >>_______________________________________________ >>freebsd-current_at_freebsd.org mailing list >>http://lists.freebsd.org/mailman/listinfo/freebsd-current >>To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org" >> > > > _______________________________________________ > freebsd-current_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org"Received on Mon Nov 03 2003 - 23:29:33 UTC
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