About documentation...

Posted Jul 25, 2007 23:38 UTC (Wed) by i3839 (guest, #31386)
In reply to: About documentation... by mingo
Parent article: Interview with Con Kolivas (APC)

Interesting info. But nothing about the fields I asked about. ;-)

Anyway, if those knobs only appear with CONFIG_SCHED_DEBUG enabled, I think it's better to document them in the Kconfig entry than in that documentation file. That way people interested in it can find it easily, and if the debug option ever disappears the help file won't need to be updated. When deciding whether to enable an option people look at the Kconfig text, so give all info they need to know there.

sum_exec_runtime/sum_wait_runtime seems also interesting. The ratio is 1 to 1442 for ksoftirqd (it ran for 5 ms and it waited 7 seconds for that, ouch). While wait_runtime_overruns is 232 and zero underruns. (Sure those fields aren't swapped accidentally?)

events/0 info is also interesting, it has a se.block_max of 1.1 second, which seems suspiciously high.

se.wait_runtime inclused the time a task slept, right? Otherwise it should be zero for all tasks that are sleeping, and that isn't the case.

Another strange thing is that really a lot tasks have almost the same block_max of 1.818 or 1.1816 seconds. The lower digits are so close together that it seems like all tasks were blocked and unblocked at the same time. Oh wait, that is probably caused by resume from/suspend to ram.