I have a system running CentOS 5.9 and DAHDI 2.6.2 with a 2-port E1 card using the wct4xxp driver (also using Asterisk 11.5.0, but that isn’t relevant to the question).
With DAHDI and Asterisk started, the system appears to run normally, as far as I can tell from limited testing.
I am monitoring User, System and Nice CPU usage using SNMP and MRTG, and I
have noticed that when I have started up DAHDI, the System CPU jumps up to around 12% or so and stays there. It does this even if I don’t start Asterisk.
On previous systems I have built over the years, using CentOS4 and Zaptel, I don’t recall seeing such high CPU usage just from having Zaptel started. It would be down near 0% until the system started handling real calls.
So my first question would be: is this high CPU usage normal with current cards and DAHDI? It’s curious that 12.5% is 1/8 of 100% and /proc/cpuinfo reports 8 CPUs, but I don’t know whether that is just coincidence. The CPU
is a X3450 with four cores and HT enabled.
Any thoughts would be gratefully received!