This is a duplicate of https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=171811 created at the request of gonzo@, so that we can close the old one from 2012. I don’t know how the original Issue maker lives (ben@desync.com), but I'm still alive. So, I'll do it. All information from the old issue is relevant and affects all the "supported" versions of FreeBSD in 2019: more info how to reproduce: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=171811#c3
Can you freshly describe the problem and provide some reproduction steps?
RACCT pcpu metrics are incorrect when processes end quickly. What i expect: maximum value for 1-core process: 100 What i get: 100x256 It is not an artificial or abstract state. For example this behavior is easy to see when working 'make config' for autotools with the launch of a lot of short calls (e.g env BATCH=no make -C /usr/ports/misc/mc clean configure). This makes it impossible to use any external billing based on RACCT. How to reproduce ( we use cpuset here to create load on only one core. So we should have pcpu=100 for jail assuming the jail does nothing else ): 1) Run jail1 2) Try to execute ant fast/light external command (e.g. /bin/ls ) in the loop. For more convincing create a simple utility: --- #include <stdio.h> int main() { return 0; } --- Write execution loop and drop it into jail, e.g /root/run.sh: --- #!/bin/sh while [ 1 ]; do /root/a.out > /dev/null done --- Run inside jail this script via cpuset: cpuset -c -l 0 /bin/sh /root/run.sh After this we can see on the 'top -P' something like: --- 182 processes: 2 running, 180 sleeping CPU 0: 34.1% user, 0.0% nice, 65.9% system, 0.0% interrupt, 0.0% idle CPU 1: 0.5% user, 0.0% nice, 0.0% system, 0.0% interrupt, 99.5% idle CPU 2: 3.1% user, 0.0% nice, 1.2% system, 0.0% interrupt, 95.7% idle CPU 3: 0.0% user, 0.0% nice, 0.4% system, 0.0% interrupt, 99.6% idle CPU 4: 1.2% user, 0.0% nice, 0.8% system, 0.0% interrupt, 98.1% idle CPU 5: 0.8% user, 0.0% nice, 0.4% system, 0.0% interrupt, 98.8% idle CPU 6: 1.2% user, 0.0% nice, 0.0% system, 0.0% interrupt, 98.8% idle CPU 7: 0.4% user, 0.0% nice, 0.4% system, 0.0% interrupt, 99.2% idle ... PID USERNAME THR PRI NICE SIZE RES STATE C TIME WCPU COMMAND 41437 root 1 76 0 11408K 2232K CPU0 0 0:07 12.79% sh ... --- Only one core is busy. However if we look at the RACCT from the hoster side, we see the following: freebsd:~ # rctl -u jail:jail1 | grep pcpu pcpu=25600 freebsd:~ # rctl -u jail:jail1 | grep pcpu pcpu=25600 freebsd:~ # rctl -u jail:jail1 | grep pcpu pcpu=25600
I've created a patch here: https://reviews.freebsd.org/D30632 which seems to fix this problem.
(In reply to cyril from comment #3) I confirm - everything is fine now. Tested on: FreeBSD 14.0-CURRENT #0 main-n247127-1976e079544-dirty amd64