* Karsten Wiese <fzu@xxxxxxxxxxxxxxxxxxxxx> wrote: > Similar weirdness here on rc6-mm2 and rc6-rt*: resume from disk waits > unduly long. i'm wondering whether the jiffies update fix from Thomas fixes this bug for you. If not then do you have a serial console enabled? > Some waiting times from rc6-rt6 from memory: > > Config | HZ | NO_HZ + HRESTIMERS > cmos clock unchanged | 2s | 6s > cmos clock += 10min | | 2 minutes > cmos clock += 2 month | 20s | > 4minutes, test interrupted i've seen something like this on -rt (and incorrectly attributed it to -rt) when running on a system which has a serial port and which has a kernel console on that serial port. What happens is that after resume (and straight after console suspend) every serial character printed takes /alot/ of time - and resume does print a number of kernel messages to the console. I didnt get any further in debugging this though, but disabling the serial console made the problem go away. a possibly related thing: the serial code is sensitive to jiffies updates and timers, i saw that during early revisions of the dynticks code - but the specifics escape me. the slowdown could also be something like the kernel somehow wrapping around jiffies and thus doing /alot/ of jiffy ticks? Or it could be a miscalculation in the amount of jiffies that need updating, resulting in a similar number of loops in the jiffy update code. (i'll try to figure out this regression - but wanted to describe to you the known things so far, maybe you'll figure it out faster than me.) Ingo - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
