Am 11.05.2015 7:31 nachm. schrieb Anton Ivanov <anton.iva...@kot-begemot.co.uk>: > > On 11/05/15 18:20, Anton Ivanov wrote: > > On 11/05/15 18:00, Thomas Meyer wrote: > >> Hi, > >> > >> maybe there is a bug in how the timers are created for all user space > >> processes. > >> In the latest patch I use os__timer_remain for the initial interval. > >> The idea was to launch all timers at the same time. But I now think this > >> can never work using relative times, especially when os__timer_remain > >> returns 0, then the new timer is never launched. > > That is not a bad idea, just requires a more complex check in setting up > > interval so it is reset to default when a zero value or value > HZ is > > passed. > > > > > >> That may explain the hangs you see. > >> You could try to replace os__timer_remain with the current HZ value in > >>nanoseconds. > > I am going to adjust time.c instead as above. > > Both approaches fail - the check (that is expected actually, I did not > think properly here - it does not cover the stub in kernel/skas) and the > setting of data to the correct initial values. > > Also, if it was just not starting timers it would have been possible to > beat the process with USR2 on the head until its morale improves. Well, > "while true; do kill -USR2 PID ; done" does not change the behavior, it > still hangs and is still possible to terminate the errant process by > sending SIGSEGV to the UML thread which is shown as 100% CPU and in R state.
Yes, sending USR2 should do the same. Correct. > > Problem is somewhere else. I am surprised it worked correctly in the > original one as there for 100% flat CPU usage it should have converged > to a behavior which is similar to what we have now. Mhh. Strange. Any hints how I can reproduce this? I need to see the same behaviour, i.e. the hang on my machine to begin to understand what is going on here. Thanks for testing Anton. > > A. > > > > > A. > > > >> Kind regards > >> Thomad > >> > >> A > > [snip] > > > > A. > > > > ------------------------------------------------------------------------------ > > > > One dashboard for servers and applications across Physical-Virtual-Cloud > > Widest out-of-the-box monitoring support with 50+ applications > > Performance metrics, stats and reports that give you Actionable Insights > > Deep dive visibility with transaction tracing using APM Insight. > > http://ad.doubleclick.net/ddm/clk/290420510;117567292;y > > _______________________________________________ > > User-mode-linux-devel mailing list > > User-mode-linux-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel > > > > > ------------------------------------------------------------------------------ > > One dashboard for servers and applications across Physical-Virtual-Cloud > Widest out-of-the-box monitoring support with 50+ applications > Performance metrics, stats and reports that give you Actionable Insights > Deep dive visibility with transaction tracing using APM Insight. > http://ad.doubleclick.net/ddm/clk/290420510;117567292;y > _______________________________________________ > User-mode-linux-devel mailing list > User-mode-linux-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
