On Fri, 2007-10-05 at 12:26 -0400, Matthew J. Roth wrote: > Alan Lord wrote: > > I'm building a test asterisk server and building the latest kernel I got > > to wonder if there are any specific recommendations about schedulers and > > so forth for optimum performance. > > > > There are a few areas that raise questions in my mind and I wonder if > > anyone has any opinions/comments on which settings are most suitable for > > use with asterisk: > > > > SLAB Allocator (SLAB or SLUB?) > > Tickless System (?) > > Preemption model (?) > > IO Scheduler (Anticipatory, Deadline or CFQ?) > > Flat or Sparse Memory (?) > > Timer Frequency (100Hz .. 1000hz) > > > Alan, > > Good post! I've wondered about the preemption model and I/O scheduler > myself, so I'll be keeping an eye on this thread. As the Linux kernel > evolves to allow configuration as a fully deterministic real-time OS, it > will be interesting to see what settings provide the optimal environment > for Asterisk. > > As for my contribution to the thread, I have a few tips for configuring > the kernel if you plan on using ztdummy for timing: > > 1. The kernel version must be at least 2.6.13 > 2. The kernel must be configured with a timer frequency of 1000 HZ > 3. The kernel must be configured to provide RTC interrupts
No kernel expert here but I don't think that RTC support is necessary if you have a recent kernel with high resolution timer support. There is support in the 1.2 svn tree for these high res timers. I tried them on an updated Fedora 7 box and the zttest results were better than when using the RTC stuff. > 4. The kernel must be configured with enhanced real time clock support See previous remark :) > Remember to use zttest to verify the accuracy of your timing source. > The goal is to obtain at least 99.98% output from zttest On the Fedora 7 box with high res timers the output of zttest shows 100% many times while with RTC I have never seen 100% but usually something between 99,97% and 99,98%. All I can say is try it and see for yourself. Regards, Patrick _______________________________________________ --Bandwidth and Colocation Provided by http://www.api-digital.com-- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users