Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 27 Jun 2020 22:39:59 +0000
From:      bugzilla-noreply@freebsd.org
To:        bugs@FreeBSD.org
Subject:   [Bug 247602] top occasionally shows unrealistic WCPU values
Message-ID:  <bug-247602-227@https.bugs.freebsd.org/bugzilla/>

next in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D247602

            Bug ID: 247602
           Summary: top occasionally shows unrealistic WCPU values
           Product: Base System
           Version: 11.4-RELEASE
          Hardware: amd64
                OS: Any
            Status: New
          Severity: Affects Only Me
          Priority: ---
         Component: bin
          Assignee: bugs@FreeBSD.org
          Reporter: jdc@koitsu.org

Preface: this is a different problem than what's in PR 135823 (threading is=
 not
involved in this one, at least not as far as the processes themselves go), =
and
what's in PR 236096 (I use SCHED_ULE).  (I've picked 11.4-RELEASE for the
Version field in Bugzilla because that's the closest to stable/11 I can get=
.)

While building world (make -j2 buildworld) on a 2-core 11/stable (r358258)
amd64 VM I have, while running top -s 1, I noticed  on very rare occasion --
but recurring -- some procesesses would show completely ridiculous WCPU val=
ues.
 The numbers of processes which would show this varied (sometimes an entire
page worth, other times only partial numbers).  Most of these processes do =
not
have threads, in case that's relevant.  Example:

  PID USERNAME    THR PRI NICE   SIZE    RES STATE   C   TIME    WCPU COMMA=
ND
 1211 halbot        1  20    0 56524K 50092K select  1   0:01
1830297421127995.00% perl /home/halbot/hal/halbot.pl
/home/halbot/hal/halbot.json
  764 jdc           1  20    0 13208K  5748K select  0   0:00
1830297421127995.00% sshd: jdc@pts/0 (sshd)
  486 unbound       1  20    0 19320K  9672K kqread  1   0:00
1830297421127995.00% /usr/local/sbin/unbound -c
/usr/local/etc/unbound/unbound.conf
  905 root          1  20    0  5024K  1372K select  1   0:00
1830297421127995.00% make -m /usr/src/share/mk -f Makefile.inc1 TARGET=3Dam=
d64
TARGET_ARCH=3Damd64 buildworld
  881 root          1  20    0  5024K   984K select  1   0:00
1830297421127995.00% make -j2 buildworld
 4091 root          1  52    0  5024K  1780K select  1   0:00
1830297421127995.00% make DIRPRFX=3Dusr.bin/clang/llvm-tblgen/ all
  465 root          1  20    0  6428K  1996K select  1   0:00
1830297421127995.00% /usr/sbin/syslogd -4 -s -s -cc
 4240 root          1  80    0   156M   135M CPU1    1   0:03 100.71%
/usr/bin/c++ -cc1 -triple x86_64-unknown-freebsd11.3 -emit-obj -disable-free
-disable-llvm-verifier -discard-value
 4237 root          1  80    0   164M   142M RUN     0   0:04  99.76%
/usr/bin/c++ -cc1 -triple x86_64-unknown-freebsd11.3 -emit-obj -disable-free
-disable-llvm-verifier -discard-value
 4216 jdc           1  20    0  7928K  2900K CPU0    0   0:00   0.09% top
  568 root          1  20    0   105M 95940K select  1   0:02   0.03%
/usr/local/bin/perl -T -w /usr/local/bin/spamd -4 -c -d -r
/var/run/spamd/spamd.pid
 1493 jdc           1  20    0 13208K  5776K select  1   0:00   0.02% sshd:
jdc@pts/1 (sshd)
  656 root          1  20    0   145M  6172K kqread  0   0:00   0.01% php-f=
pm:
master process (/usr/local/etc/php-fpm.conf) (php-fpm)
...


This looks like an overflowed integer, but makes me wonder if the bug is in=
 the
kernel or in top itself.  (Not sure if this should be Component: bin or
Component: kern)

I might suggest pulling jhb@ in for this one since he has great familiarity
with some of top's code, esp. relating to WCPU.

--=20
You are receiving this mail because:
You are the assignee for the bug.=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-247602-227>