Hello everyone,
I'm currently trying to run an Asterisk server in a Xen kernel under
Dom0 (debian kernel 2.6.18 with xen hypervisor 3.0.4). I had read of
some possible timing issues with ztdummy (using rtc) under DomU, but I
have a zaptel compatible PCI card (TDM400P), and I experience big
problems with IRQ misses every time there is a bit of load on the server
(for example, when an HVM DomU is running). The card is supposed to
report 1000 interruptions per second, but it doesn't, and consequences
are horrible crackling sound in communications. Running the utility
zttest to check for the stability of those interrupts under a small bit
of load, i get:
# ./zttest
Opened pseudo zap interface, measuring accuracy...
99.609375% 99.609375% 99.218750% 99.316406% 99.804688% 99.414062%
99.121094%
99.511719% 99.121094% 99.316406% 99.707031% 99.707031% 98.730469%
99.414062% 99.902344%
99.218750% 100.000000% 99.414062% 98.828125% 99.218750% 99.316406%
98.449707% 100.000000%
(from digium: results should be >= 99.98 in order not to have sound
problems)
I tried about everything I could find on Asterisk documentation: moving
PCI slots, noapic and acpi=off boot options, play with different kernel
options: iosched/preemption/timer/..., play with BIOS PCI options, PCI
latencies, IRQ balance, smp_afinity, ................ but impossible to
come up with anything correcting that problem.
I then mailed to Asterisk user mailing list and they told me:
"Xen has many, many problems with interrupt handling and is utterly
unsuitable for running anything that depends on hardware peripherals. I
speak from very painful experience.
There is no way, under any circumstance, that I would try to run
Asterisk with interface cards in a Xen environment. It's too bad you
wasted so much time trying to fix it -- it's never going to work."
Does anyone have an idea of how to possibly resolve this issue, or
should I really abandon the idea using Xen and Asterisk together?
# xm info
host : sol
release : 2.6.18
version : #3 SMP Fri May 11 11:32:34 CEST 2007
machine : x86_64
nr_cpus : 2
nr_nodes : 1
sockets_per_node : 1
cores_per_socket : 2
threads_per_core : 1
cpu_mhz : 2009
hw_caps :
178bfbff:e3d3fbff:00000000:00000010:00000001:00000000:00000003
total_memory : 2047
free_memory : 136
xen_major : 3
xen_minor : 0
xen_extra : .3-1
xen_caps : xen-3.0-x86_64
xen_pagesize : 4096
platform_params : virt_start=0xffff800000000000
xen_changeset : Tue Oct 17 22:09:52 2006 +0100
cc_compiler : gcc version 4.1.2 20061028 (prerelease) (Debian
4.1.1-19)
cc_compile_by : ultrotter
cc_compile_domain : debian.org
cc_compile_date : Fri Nov 3 00:21:27 CET 2006
xend_config_format : 2
# cat /proc/interrupts
CPU0 CPU1
1: 94 0 Phys-irq i8042
6: 3 0 Phys-irq floppy
8: 0 0 Phys-irq rtc
9: 0 0 Phys-irq acpi
14: 63 0 Phys-irq ide0
16: 1 0 Phys-irq libata, eth3
17: 532462 0 Phys-irq libata
18: 4102 0 Phys-irq libata
19: 493234 0 Phys-irq sky2, eth0
20: 689908 0 Phys-irq eth1
21: 5559727 0 Phys-irq wctdm
256: 3022027 0 Dynamic-irq timer0
257: 522260 0 Dynamic-irq resched0
258: 43 0 Dynamic-irq callfunc0
259: 0 432127 Dynamic-irq resched1
260: 0 106 Dynamic-irq callfunc1
261: 0 1743951 Dynamic-irq timer1
262: 1020 0 Dynamic-irq xenbus
263: 0 0 Dynamic-irq console
NMI: 0 0
LOC: 0 0
ERR: 0
MIS: 0
Thanks,
François.
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
Home