https://bugzilla.kernel.org/show_bug.cgi?id=12114 --- Comment #9 from Dominique Larchey-Wendling <larchey@xxxxxxxx> 2011-03-07 12:58:38 --- Two years later, here are my observations regarding the TSC/network/skge problem. After I disabled cpu frequency scaling AND the processor option in ACPI (ACPI_PROCESSOR=n), the TSC was not unstable any more on a 2.6.27 kernel (patch with openvz). The file server has been running flawlessly for more than a year without reboot, sometimes under heavy load for weeks long. No more stalled network interface leading to an inaccessible server (the server is headless). 2 weeks ago, I updated the server to FC14 and a 2.6.32 kernel (patch with openvz). As I did not recall the whole TSC problem issues, I inadvertently changed the ACPI_PROCESSOR flag to y(es), but as I remembered that frequency scaling was an issue, I let that option untouched, ie no frequency scaling. As a consequence, the network stalling problem re-appeared. After a few days of uptime (1 to 3 days), the file server network interface does not respond any more, but there is no crash, no oops. I noticed the following message in the logs : Mar 7 09:59:47 xxxxx klogd: [ 4.100585] Marking TSC unstable due to TSC halts in idle And thus tsc is removed from /sys/devices/system/clocksource/clocksource0/available_clocksource Only acpi_pm remains. But nevertheless, even though TSC is removed as a clock source, it seems that the TSC functionality is not completely ignored and has a bad impact on the behaviour of the skge driver. After I re-read this bugzilla thread, I remembered the ACPI_PROCESSOR issue and I disabled it again. Now TSC is apparently stable and serves as "reliable" clock source. Also, hopefully, the skge driver will work again. Otherwise I will come back here. I cannot test later kernels like 2.6.36 or 2.6.37 because no openvz patch exists for such kernels. I don't know if "unstable TSC" management has evolved in recent kernels. What remains a mystery for me is how an unstable but disabled TSC (as a clock source) impacts the skge network driver. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
