On Sat, 7 Nov 2015, Ian Smith wrote:
... I also notice that with HPET, the timer interrupts themselves, whether as few as 60-70/s idle in one-shot mode or ~2000/s in periodic, appear in systat -vm or vmstat -w10 'Int' column, whereas with LAPIC or (yes I even tried) i8254, these timer interrupts don't count in that column.
Interrupt reporting is mostly broken for "fast" interrupts. E.g., systat -v counts them in the Interrupts column (separate and Total) but not in the Int summary; vmstat -m doesn't count them anywhere (it shows the Int summary). vmstat -i shows them much like the Interrupts column in systat -v (except it actually displays them all when there are too man CPUs or Interrupts to fit in systat -v). I use COUNT_IPIS and COUNT_XINVLTLB. The interrupts counted by these are actually fast. These mess up the systat -v display by giving too many active interrupts to display for just a couple of CPU. systat -v tends to display these in preference to more interesting interrupts. vmstat -i displays these too. "fast" and fast interrupts should be counted separately and are probaly best left out of the Int summary. They should also be displayed separately.
I'll try Hans' suggestion of adjusting in loader.conf, rebooting between various options if really needed, though that'll be far more tedious .. [ I've just now seen Bruce's latest, so maybe I haven't been doing the wrong thing playing with these after all? ]
The eventtimer choice is readonly, so rebooting seems to be required to change it. Too much like Windows. I often miss being able to change hz. Event timers now do much more complicated changes than that. They implement a sort of dynamic hz, but still use the boot-time hz as a default. Bruce _______________________________________________ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
