Tharindu Rukshan Bamunuarachchi wrote: > Dear All, > > In summary, Vanilla Linux kernel gives average 3-4ms response time. > But, when CONFIG_PREEMPT is turned on response is improved > dramatically. Less than 100us (microseconds). I love that value. > > > I have tried Three Different Linux kernels. > > 1. Vanilla 2.6.9x > 2. Vanilla + CONFIG_PREEMPT Enabled > 3. Vanilla + Preemptible Patch > > For each case I got following latencies in worst and best situations. > > 1. Vanilla --------------------------- Best(2000us) > Worst(~20000us) > 2. CONFIG_PREEMPT ------- Best(75us) Worst(700us) > > > Actually all of above test were carried out using in-house small test > program. > Test program has two components and Server wakes up when client send > some data. > We are measuring Round Trip Time from client to server.Above values > are in us = microsecond. > > Actually, change of HZ value makes kernel unstable. I saw there are > kernel code segments which assumes HZ value is either 1000, 250 or > 512?? . However increase of HZ made kernel more responsive. > > I am going to use 1000 HZ and CONFIG_PREEMPT for while. In next few > days I will try to carry out some more performance test with > Preemptible Patch and RT Linux. > > Let you know the results of This Great Kernel. > > > Like to thank all of your help and kind response to my mails. > For a good test of your system see. ftp://ftp.compro.net/public/rt-exec/rt-exec-1.0.3.tar.bz2 Mark -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
