-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Thu, 2 Mar 2006, Nathan Hawkins wrote: > Bartek Kania wrote: >> Those are great results! >> I don't know how xen handles scheduling but I'm always careful with >> anything that might add latency to the scheduling or timing. 1ms >> resolution is the minimum needed (a little less can be accepted since >> jitterbuffers can usually handle that). > Xen has a realtime scheduler called SEDF, which I was using. It's > slightly over my head, and I'm not sure I'm doing everything right yet. > But I'm essentially running Linux inside a realtime scheduler. It would > seem however, that Xen is capable of dealing with the timers OpenPBX is > using, because I ran Asterisk with the same configuration, and the > results were unacceptable.
That's good. I know next to nothing about Xen, but it seems it's the perfect way to virtualize pbxes. > I used scheduling parameters that according to the Xen documentation > tell it to make that Linux instance have a 5ms slice every 20ms. (In > fact, I used an example out of the documentation.) We use RTP with ulaw > 20ms packets. Does OpenPBX actually need to wakeup every 1ms, or does it > need to wakeup every 20ms with better than 1ms resolution? It needs to wake up every 20ms with 1ms (or better) precision. I don't think there is anything currently that requires waking up every 1ms in opbx. In zaptel, and possibly others, the driver needs to react that fast if I'm not mistaken. >> Did you use the -p option to opbx (it makes it run with higher priority)? > Yes. Unfortunately, building XenLinux kernels disables CONFIG_PREEMPT, > or I'd have turned that on too. That's too bad. But it seems to work anyway which is good. CONFIG_PREEMPT will mostly be an issue if you do lots of disk io and stuff in the same domain and openpbx needs to run. If it doesn't then xens realtime scheduler should deal with the scheduling. Which it seems to do beautifully. /B - -- * GPG-Key: http://evil.gnarf.org/mrbk.pgp A: Because we read from top to bottom, left to right. Q: Why should i start my reply below the quoted text? - -- http://www.i-hate-computers.demon.co.uk/ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQFEBvl5ckvkFeO3ANARAtTcAJ9/3Pyn757VnphcMqKo3512LCXa+wCeIVMD iKOaeYEBsTsGVvND4n5scBE= =MmwJ -----END PGP SIGNATURE----- _______________________________________________ Openpbx-users mailing list [email protected] http://lists.openpbx.org/mailman/listinfo/openpbx-users
