Lee David wrote: > Hi, all > > I downloaded rt-preempt patch and hrt patch, after successfully compiled > a new > kernel I ran the cyclictest three times each. As to rt vs. hrt, the result > seemed to be not that different as showed in Gleixner and Niehaus's OLS > paper > "Hrtimers and Beyond: Transforming the Linux Time Subsystem." > > Was my result below make sense? Or did I missed something? > Any comments and advices are welcome. > ---------------------------------------------------------------------- > * The following result is from the paper: > All tests have been run on a Pentium III 400MHz based PC. > Test case: clock_nanosleep(TIME_ABSTIME), interval 10000 microseconds, > 10000 loops, no load. > > Commandline: cyclictest -t 1 -p 80 -n -i 10000 -l 10000 > Kernel min max avg > 2.6.16 24 4043 1989 > 2.6.16-hrt5 12 94 20 > 2.6.16-rt12 6 40 10 > > * Here is my result: > Celeron M 370 (1.5 GHZ) w/ 512M memory. > I turned on "HPET Timer Support" for all the three cases. > For rt, I chose "Complete real-time preemption". > > kernel min max avg > 2.6.16 8 4038 2027 > 8 4055 1990 > 8 4018 1991 > 2.6.16-hrt6 16 94 62 > 17 78 61 > 11 72 63 > 2.6.16-rt29 14 79 62 > 11 74 62 > 11 71 63 > ---------------------------------------------------------------------- > rt-preempt patch: > http://people.redhat.com/mingo/realtime-preempt/older/patch-2.6.16-rt29 > > hrt patch: > http://www.tglx.de/projects/hrtimers/2.6.16/patch-2.6.16-hrt6.patch > > Cyclictest: > http://tglx.de/projects/misc/cyclictest/cyclictest-v0.11.tar.bz2 > > Thanks in advance, > D.L. Well the reason you don't really see much difference between the hrt and the rt is because your not really stressing your machine at the same time you run this. All you are really seeing is the high-res timer capabilities added to your kernel. As you probably know the rt patch does contain the hrt patch set. For a "maybe" better or more stressing test of your system you might see ftp://ftp.compro.net/public/rt-exec Mark -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
