Re: td_swvoltick
On 01/12/2018 13:36, Konstantin Belousov wrote: > On Fri, Jan 12, 2018 at 01:31:41PM -0600, Eric van Gyzen wrote: >> should_yield() compares thread::td_swvoltick to 'ticks' to determine >> whether a thread is hogging and should yield. Since td_swvoltick >> records 'ticks' /before/ the actual context switch, the calculation in >> should_yield() includes any time that the thread was switched out. It >> seems that should_yield() wants to know how long the thread has actually >> been running. Therefore, td_swvoltick should record 'ticks' /after/ >> sched_switch() returns. >> >> Does this make sense, or am I missing something? > Yes, it does make sense to me. Thanks, Kostik. If anyone else is interested: https://reviews.freebsd.org/D13892 >> >> If this makes sense, I would probably keep the current assignment in >> mi_switch() and simply add a second assignment after the call to >> sched_switch(). That way, db_show_thread will still show useful data >> for sleeping threads. I would do the same for td_swinvolticks. >> >> I'll be happy to make the change myself. I just want a sanity check >> before I bother. >> >> Thanks in advance, >> >> Eric ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: td_swvoltick
On Fri, Jan 12, 2018 at 01:31:41PM -0600, Eric van Gyzen wrote: > should_yield() compares thread::td_swvoltick to 'ticks' to determine > whether a thread is hogging and should yield. Since td_swvoltick > records 'ticks' /before/ the actual context switch, the calculation in > should_yield() includes any time that the thread was switched out. It > seems that should_yield() wants to know how long the thread has actually > been running. Therefore, td_swvoltick should record 'ticks' /after/ > sched_switch() returns. > > Does this make sense, or am I missing something? Yes, it does make sense to me. > > If this makes sense, I would probably keep the current assignment in > mi_switch() and simply add a second assignment after the call to > sched_switch(). That way, db_show_thread will still show useful data > for sleeping threads. I would do the same for td_swinvolticks. > > I'll be happy to make the change myself. I just want a sanity check > before I bother. > > Thanks in advance, > > Eric > ___ > freebsd-current@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org" ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
td_swvoltick
should_yield() compares thread::td_swvoltick to 'ticks' to determine whether a thread is hogging and should yield. Since td_swvoltick records 'ticks' /before/ the actual context switch, the calculation in should_yield() includes any time that the thread was switched out. It seems that should_yield() wants to know how long the thread has actually been running. Therefore, td_swvoltick should record 'ticks' /after/ sched_switch() returns. Does this make sense, or am I missing something? If this makes sense, I would probably keep the current assignment in mi_switch() and simply add a second assignment after the call to sched_switch(). That way, db_show_thread will still show useful data for sleeping threads. I would do the same for td_swinvolticks. I'll be happy to make the change myself. I just want a sanity check before I bother. Thanks in advance, Eric ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
