Frank Sorenson wrote: > Tony Lindgren wrote: > | * Tony Lindgren <[EMAIL PROTECTED]> [050407 23:28]: > | > |>I think I have an idea on what's going on; Your system does not wake to > |>APIC interrupt, and the system timer updates time only on other > interrupts. > |>I'm experiencing the same on a loaner ThinkPad T30. > |> > |>I'll try to do another patch today. Meanwhile it now should work > |>without lapic in cmdline. > | > | > | Following is an updated patch. Anybody having trouble, please try > | disabling CONFIG_DYN_TICK_USE_APIC Kconfig option. > | > | I'm hoping this might work on Pavel's machine too? > | > | Tony > > This updated patch seems to work just fine on my machine with lapic on > the cmdline and CONFIG_DYN_TICK_USE_APIC disabled. > > Also, you were correct that removing lapic from the cmdline allowed the > previous version to run at full speed. > > Now, how can I tell if the patch is doing its thing? What should I be > seeing? :) > > Functionally, it looks like it's working. There were a number of > compiler warnings you might wish to fix before calling it good. Such as > "initialization from incompatible pointer type" several times in > dyn-tick-timer.c and a "too many arguments for format" in > dyn_tick_late_init. >
Here are some figures about idle/C-states: Passing bm_history=0xF to processor module makes it going into C3 and deeper. Passing lower values, deeper states are reached more often, but system could freeze: bm_activity=0x4 bus master activity: fefffffd states: C1: type[C1] promotion[C2] demotion[--] latency[001] usage[00000010] *C2: type[C2] promotion[C3] demotion[C1] latency[001] usage[00007183] C3: type[C3] promotion[C4] demotion[C2] latency[085] usage[00000515] C4: type[C3] promotion[--] demotion[C3] latency[185] usage[00000330] bm_activity=0x1 bus master activity: ffff7ffd states: C1: type[C1] promotion[C2] demotion[--] latency[001] usage[00000010] *C2: type[C2] promotion[C3] demotion[C1] latency[001] usage[00005495] C3: type[C3] promotion[C4] demotion[C2] latency[085] usage[00000537] C4: type[C3] promotion[--] demotion[C3] latency[185] usage[00000472] Figures NO_IDLE_HZ disabled, HZ=1000 (max sleep 1ms) (Don't trust the figures too much, there probably are little bugs...): Active C0/C1 state: Total(ms): 145 Usage: 20205 Failures: 0 Maximum(us): 1967 Average(us): 7 Sleep C2 state: Total(ms): 19306 Usage: 20074 Failures: 0 Maximum(us): 1275 (-> strange max should be 1000us) Average(us): 961 Sleep C3 state: Total(ms): 34 Usage: 131 Failures: 0 Maximum(us): 984 Average(us): 259 Measures based on ACPI PM timer reads Total switches between C-states: 20205 Switches between C-states per second: 1063 per second Total measure time (s): 19 Total measure time (based on starting measures) (s): 20 Figures NO_IDLE_HZ enabled, processor.bm_history=0xF HZ=1000: (Don't trust the figures too much, there probably are little bugs...): Active C0/C1 state: Total(ms): 81 Usage: 4659 Failures: 0 Maximum(us): 1608 Average(us): 17 Sleep C2 state: Total(ms): 71108 Usage: 4241 Failures: 0 Maximum(us): 49921 Average(us): 16766 Sleep C3 state: Total(ms): 219 Usage: 167 Failures: 0 Maximum(us): 28296 Average(us): 1311 Sleep C4 state: Total(ms): 374 Usage: 251 Failures: 0 Maximum(us): 18870 Average(us): 1490 Measures based on ACPI PM timer reads Total switches between C-states: 4659 Switches between C-states per second: 65 per second Total measure time (s): 71 Total measure time (based on starting measures) (s): 75 I buffer C-state times in an array and write them to /dev/cstX. >From there I calc the stats from userspace. Tony: If you like I can send you the patch and dump prog for http://www.muru.com/linux/dyntick/ ? I try to find a better algorithm (directly adjust slept time to C-state latency or something) for NO_IDLE_HZ (hints are very welcome) and try to come up with new figures soon. Thomas - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/