Re: [PATCH 0/4] Rework alarm timer infrastrucure - take2

Luca Tettamanti
2007-08-22T16:12:11Z

Il Wed, Aug 22, 2007 at 08:02:07AM +0300, Avi Kivity ha scritto:
> Luca Tettamanti wrote:
>
> > Actually I'm having troubles with cyclesoak (probably it's calibration),
> > numbers are not very stable across multiple runs...
> >
>
> I've had good results with cyclesoak; maybe you need to run it in
> runlevel 3 so the load generated by moving the mouse or breathing
> doesn't affect meaurements.

This is what I did, I tested with -no-grapich in text console.

> > The guest is an idle kernel with HZ=1000.
> >
>
> Can you double check this? The dyntick results show that this is either
> a 100Hz kernel, or that there is a serious bug in dynticks.

Ops I sent the wrong files, sorry.

This is QEMU, with dynticks and HPET:

% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
52.10 0.002966 0 96840 clock_gettime
19.50 0.001110 0 37050 timer_gettime
10.66 0.000607 0 20086 timer_settime
10.40 0.000592 0 8985 2539 sigreturn
4.94 0.000281 0 8361 2485 select
2.41 0.000137 0 8362 gettimeofday
------ ----------- ----------- --------- --------- ----------------
100.00 0.005693 179684 5024 total

% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
93.37 0.025541 3 10194 10193 select
4.82 0.001319 0 33259 clock_gettime
1.10 0.000301 0 10195 gettimeofday
0.71 0.000195 0 10196 10194 sigreturn
------ ----------- ----------- --------- --------- ----------------
100.00 0.027356 63844 20387 total

And this KVM:

% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
42.66 0.002885 0 45527 24 ioctl
25.62 0.001733 0 89305 clock_gettime
13.12 0.000887 0 34894 timer_gettime
7.97 0.000539 0 18016 timer_settime
4.70 0.000318 0 12224 7270 rt_sigtimedwait
2.79 0.000189 0 7271 select
1.86 0.000126 0 7271 gettimeofday
1.27 0.000086 0 4954 rt_sigaction
------ ----------- ----------- --------- --------- ----------------
100.00 0.006763 219462 7294 total

% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
49.41 0.004606 0 59900 27 ioctl
24.14 0.002250 0 31252 21082 rt_sigtimedwait
9.65 0.000900 0 51856 clock_gettime
8.44 0.000787 0 17819 select
4.42 0.000412 0 17819 gettimeofday
3.94 0.000367 0 10170 rt_sigaction
------ ----------- ----------- --------- --------- ----------------
100.00 0.009322 188816 21109 total

Luca
--
Runtime error 6D at f000:a12f : user incompetente