NetBSD Problem Report #50979

From www@NetBSD.org  Sat Mar 19 11:10:09 2016
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Date: Sat, 19 Mar 2016 11:10:07 +0000 (UTC)
From: prlw1@cam.ac.uk
Reply-To: prlw1@cam.ac.uk
To: gnats-bugs@NetBSD.org
Subject: dtrace -c leads to 100% cpu usage
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>Number:         50979
>Category:       port-amd64
>Synopsis:       dtrace -c leads to 100% cpu usage
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          closed
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Mar 19 11:15:00 +0000 2016
>Closed-Date:    Sun Oct 01 07:50:38 +0000 2017
>Last-Modified:  Sun Oct 01 07:50:38 +0000 2017
>Originator:     Patrick Welche
>Release:        7.99.26/amd64
>Organization:
>Environment:
>Description:
As per http://mail-index.netbsd.org/netbsd-users/2016/03/11/msg018156.html

# cat foo.d
proc:::exec
{
        trace("hello");
        exit(0);
}
# dtrace -s foo.d                           Then type "ls" in another xterm
dtrace: script 'foo.d' matched 1 probe
dtrace: buffer size lowered to 2m
CPU     ID                    FUNCTION:NAME
  2      6                            :exec   hello

# dtrace -s foo.d -c ls

and in other xterm top shows:

  PID USERNAME PRI NICE   SIZE   RES STATE      TIME   WCPU    CPU COMMAND
  738 root      29    0    52M   11M CPU/3      0:54 99.17% 92.53% dtrace

Running "ls" in another xterm just in case doesn't stop it. Finally:

^Csorry, pid 554 was killed: orphaned traced process

I was expecting "-c ls" to run /bin/ls after the proc:::exec probe was set...

>How-To-Repeat:
see above
>Fix:

>Release-Note:

>Audit-Trail:

State-Changed-From-To: open->closed
State-Changed-By: prlw1@NetBSD.org
State-Changed-When: Sun, 01 Oct 2017 07:50:38 +0000
State-Changed-Why:
I can no longer reproduce this.


>Unformatted:

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