On Thu, Aug 17, 2017 at 9:17 AM, Liang, Kan <kan.liang@xxxxxxxxx> wrote: > > We tried both 12 and 16 bit table and that didn't make a difference. > The long wake ups are mostly on the same page when we do instrumentation Ok. > Here is the wake_up_page_bit call stack when the workaround is running, which > is collected by perf record -g -a -e probe:wake_up_page_bit -- sleep 10 It's actually not really wake_up_page_bit() that is all that interesting, it would be more interesting to see which path it is that *adds* the entries. So it's mainly wait_on_page_bit_common(), but also add_page_wait_queue(). Can you get that call stack instead (or in addition to)? Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>