When a process is running for a long time (several days) time counter per process stops on value: ru_utime.tv_sec:305221 ru_utime.tv_usec:322735 Fix: No idea - may be something is wrongly calculated in kernel ??? How-To-Repeat: write something like this: void main() { struct rusage rus; while (1) { .. do something that uses the processor for a few minutes - loop with some calculations ... getrusage(RUSAGE_SELF,&rus); printf("ru_utime.tv_sec:%ld | ru_utime.tv_usec:%ld",rus.ru_utime.tv_sec,rus.ru_utime.tv_usec); } } compile and run then wait about 305000s (about 3.5 days)
On Thu, 17 Mar 2005, Jakub Kruszona-Zawadzki wrote: >> Description: > When a process is running for a long time (several days) time counter per process stops on value: > ru_utime.tv_sec:305221 > ru_utime.tv_usec:322735 This may be the same bug as in PR 76972. Overflow occurs at about 48592008 ticks = 379625 seconds = 105 hours for a a process that consumes 100% of the CPU if the statclock frequency is 128 Hz (which is the default and not easy to change). There is another overflow bug at 2^32 ticks = 388 days. This one is harder to fix. See PR 76972 for details and a fix for the first overflow bug. 37965 seconds is a little larger than 305221 seconds. The difference might be due to the other 70000+ seconds being in ru_stime. The behaviour when overflow occurs is undefined, but stopping on a value is quite likely to occur due to the algorithm for updating ru_*time. Integer overflow tends to cause counters to reset to 0 (or INT_MIN), but the kernel enforces monotonicity of the usage times, so they will stick instead of going backwards to 0. Bruce
On Thu, 17 Mar 2005, Jakub Kruszona-Zawadzki wrote: >> Description: > When a process is running for a long time (several days) time counter per process stops on value: > ru_utime.tv_sec:305221 > ru_utime.tv_usec:322735 This may be the same bug as in PR 76972. Overflow occurs at about 48592008 ticks = 379625 seconds = 105 hours for a a process that consumes 100% of the CPU if the statclock frequency is 128 Hz (which is the default and not easy to change). There is another overflow bug at 2^32 ticks = 388 days. This one is harder to fix. See PR 76972 for details and a fix for the first overflow bug. 37965 seconds is a little larger than 305221 seconds. The difference might be due to the other 70000+ seconds being in ru_stime. The behaviour when overflow occurs is undefined, but stopping on a value is quite likely to occur due to the algorithm for updating ru_*time. Integer overflow tends to cause counters to reset to 0 (or INT_MIN), but the kernel enforces monotonicity of the usage times, so they will stick instead of going backwards to 0. Bruce _______________________________________________ freebsd-bugs@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-bugs To unsubscribe, send any mail to "freebsd-bugs-unsubscribe@freebsd.org"
*** This bug has been marked as a duplicate of bug 76972 ***