Messages in this thread | | | Date | Tue, 28 Sep 1999 14:26:17 +0200 | From | Harald Koenig <> | Subject | Re: Clock Watching the Scheduler 2.2.10unip |
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On Sep 27, Richard B. Johnson wrote:
> > 1) 500 interrupts take 5 seconds. No surprise there. Except
when pressing the shift key jsut after starting `clockwatcher' it takes only 3.9 seconds: that's the 30 Hz interrupts from the keyboard.
> > 2) Most interrupts take ~5600 cycles to process on a 530 MHz Cel,
same here on a AMD K6/2-400 (DFI main board).
> > and ~2600 on 200 MHz PPro. This is better than FreeBSD > > 2.2.8 where they take ~5200 on a PPro 200. But `way longer
> Erm.. How is this supposed to measure interrupts?
it detects/measures just every delay/timeout longer than 90 cycles in this program. at least some of them have to be from interrupts and their service routines, isn't it ? playing with differnet interrupt sources shows that these `timeouts' indeed corelate with interrupt rates...
here is some data from my PC for three tests:
A: free run (X11 etc. running, 83 processes) B: like A, but shift key pressed after starting, no significant difference. C: mouse moved pretty fast all the time.
my mouse is a old Logitech serial mouse, running at 9600 baud connected to a 16450 UART (one interrupt for each character) giving ~430 interrupts/sec while moving.
in case C the run only takes ~1.1 secs for 500 `interrupts' (makes sense;) but note the longer time this interrupt service takes (6272 vs. 5632 ticks).
ticks #counts A B C
5568 1 1 0 5632 22 22 0 5696 7 7 0 5760 4 4 0 5824 5 5 0 5888 2 2 0 5952 4 4 0 6016 5 5 1 6080 6 6 25 6144 6 6 7 6208 2 2 78 6272 2 2 76 6336 0 0 60 6400 6 6 13 6464 0 0 27 6528 1 1 7 6592 1 1 0 6656 3 3 0 6720 0 0 0 6784 4 4 0 6848 1 1 2 6912 3 3 1 6976 0 0 0 7040 3 3 1 7104 0 0 0 7168 1 1 1 7232 0 0 0 7296 1 1 1 7360 0 0 1 7424 0 0 0 7488 7 7 0 7552 5 5 1 7616 12 12 0 7680 10 10 1 7744 8 8 0 7808 4 4 0 7872 5 5 0 7936 2 2 0 8000 0 0 1 8064 0 0 2 8128 1 1 8 8192 1 1 14 8256 0 0 9 8320 2 2 8 8384 3 3 7 8448 1 1 5 8512 1 1 3 8576 7 7 7 8640 1 1 2 8704 2 2 7 8768 0 0 3 8832 0 0 4 8896 0 0 1 8960 0 0 4 9024 0 0 2 9088 0 0 1 9152 0 0 1 9216 0 0 2 9280 1 1 0 9344 0 0 1 9408 1 1 0 9472 0 0 1 9536 0 0 2 9792 0 0 0 9984 0 0 0
Harald -- All SCSI disks will from now on ___ _____ be required to send an email notice 0--,| /OOOOOOO\ 24 hours prior to complete hardware failure! <_/ / /OOOOOOOOOOO\ \ \/OOOOOOOOOOOOOOO\ \ OOOOOOOOOOOOOOOOO|// Harald Koenig, \/\/\/\/\/\/\/\/\/ Inst.f.Theoret.Astrophysik // / \\ \ koenig@tat.physik.uni-tuebingen.de ^^^^^ ^^^^^
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