On Fri, 29 Jan 2016, Dmitry Vyukov wrote: > On Fri, Jan 29, 2016 at 2:57 PM, Thomas Gleixner <t...@linutronix.de> wrote: > I need something that will work without supervision. I need to use > /proc/sys/kernel/ftrace_dump_on_oops instead of > /proc/sys/kernel/traceoff_on_warning then, right? > > Quite some time? Does it dump trace from boot? In my setup kernel can > work up to an hour under super heavy parallel workload... Need to > check how it will cope with it.
The time depends on the serial speed and the trace buffer size and the number of cpus. Don't worry about the uptime. The buffer is a ringbuffer with limited capacity, so the dump time is constant. If you want that /proc/sys/kernel/ftrace_dump_on_oops spills out on warnings as well, you need to enable /proc/sys/kernel/traceoff_on_warning /proc/sys/kernel/ftrace_dump_on_oops and /proc/sys/kernel/panic_on_warn because we do not dump on warnings. Thanks, tglx