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/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=247602 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 values. 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 COMMAND 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=amd64 TARGET_ARCH=amd64 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=usr.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-fpm: 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. -- You are receiving this mail because: You are the assignee for the bug.help
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