On 11/24/2010 10:43 AM, Jonas Kellens wrote: > Hello list, > > I'm experiencing a lot of server freezes lately. The server just... freezes. > > I notice in the log files (/var/log/asterisk/messages & > /var/log/messages) that logging stops at the time the server hangs. > Logging continues when the server has been restarted (which is the only > solution). > > So it is not a proces that hangs, it's the entire server (CentOS5.5 + > Asterisk + MySQL). > > I really have no idea what can be causing these sudden freezes. Memory > stays mostly at 250MB of 512 MB total, CPU is 97% to 100% idle... > > /var/log/asterisk/debug tells me nothing, no lines that indicate > something strange before the freeze (debug level 9). > > I have no core.pid file in /tmp, when I look after rebooting the server. > > The only thing I have is a high level of mentionning of "kernel: dahdi: > Detected time shift." in /var/log/messages. > > > What is causing this kernel message ? Could this be the cause of the > server freeze ? >
When a system does not have a hardware device installed DAHDI uses the system time in order to approximate a telephony clock source (what was previously referred to as dahdi_dummy). Since it uses the system time to accomplish this, if there is a large gap in the time (typically because NTP is adjusting the time) DAHDI just reports that it thinks it's very far behind or ahead of where it should be, and doesn't even try to "mix" any audio for that interval. So, I think the "detected time shift" is more a symptom of something else causing locks as opposed to the source. Is your server keeping accurate wall-time? -- Shaun Ruffell Digium, Inc. | Linux Kernel Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com & www.asterisk.org -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users