On 07/15/16 14:19, Richard Weinberger wrote: > Hi! > > Am 15.07.2016 um 12:35 schrieb Topi Miettinen: >> Hello, >> >> There are many basic ways to control processes, including capabilities, >> cgroups and resource limits. However, there are far fewer ways to find out >> useful values for the limits, except blind trial and error. >> >> This patch series attempts to fix that by giving at least a nice starting >> point from the highwater mark values of the resources in question. >> I looked where each limit is checked and added a call to update the mark >> nearby. >> >> Example run of program from Documentation/accounting/getdelauys.c: >> >> ./getdelays -R -p `pidof smartd` >> printing resource accounting >> RLIMIT_CPU=0 >> RLIMIT_FSIZE=0 >> RLIMIT_DATA=18198528 >> RLIMIT_STACK=135168 >> RLIMIT_CORE=0 >> RLIMIT_RSS=0 >> RLIMIT_NPROC=1 >> RLIMIT_NOFILE=55 >> RLIMIT_MEMLOCK=0 >> RLIMIT_AS=130879488 >> RLIMIT_LOCKS=0 >> RLIMIT_SIGPENDING=0 >> RLIMIT_MSGQUEUE=0 >> RLIMIT_NICE=0 >> RLIMIT_RTPRIO=0 >> RLIMIT_RTTIME=0 >> >> ./getdelays -R -C /sys/fs/cgroup/systemd/system.slice/smartd.service/ >> printing resource accounting >> sleeping 1, blocked 0, running 0, stopped 0, uninterruptible 0 >> RLIMIT_CPU=0 >> RLIMIT_FSIZE=0 >> RLIMIT_DATA=18198528 >> RLIMIT_STACK=135168 >> RLIMIT_CORE=0 >> RLIMIT_RSS=0 >> RLIMIT_NPROC=1 >> RLIMIT_NOFILE=55 >> RLIMIT_MEMLOCK=0 >> RLIMIT_AS=130879488 >> RLIMIT_LOCKS=0 >> RLIMIT_SIGPENDING=0 >> RLIMIT_MSGQUEUE=0 >> RLIMIT_NICE=0 >> RLIMIT_RTPRIO=0 >> RLIMIT_RTTIME=0 >> >> In this example, smartd is running as a non-root user. The presented >> values can be used as a starting point for giving new limits to the >> service. > > I don't think it is worth sprinkling the kernel with update_resource_highwatermark() > calls just to get these metrics. > > Can't we teach the existing perf infrastructure to collect these highwatermarks for us? I don't know. What kind of changes do you think would be needed? -Topi > > Thanks, > //richard > -- 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>