NetBSD Problem Report #54841

From gson@gson.org  Tue Jan  7 12:34:58 2020
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Date: Tue,  7 Jan 2020 14:34:53 +0200 (EET)
From: gson@gson.org (Andreas Gustafsson)
Reply-To: gson@gson.org (Andreas Gustafsson)
To: gnats-bugs@NetBSD.org
Subject: time(1) reports garbage user and system times again
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>Number:         54841
>Category:       kern
>Synopsis:       time(1) reports garbage user and system times again
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Jan 07 12:35:00 +0000 2020
>Last-Modified:  Thu Jan 09 15:50:01 +0000 2020
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current
>Organization:
>Environment:
System: NetBSD
Architecture: i386
Machine: i386
>Description:

Running -current/i386 on real 8-core hardware:

# cd /usr/test/fs/vfs
# time atf-run t_vnops >log
       53.35 real    665258.06 user    146439.61 sys

>How-To-Repeat:

See above.

>Fix:

>Audit-Trail:
From: Andreas Gustafsson <gson@gson.org>
To: gnats-bugs@netbsd.org
Cc: 
Subject: Re: kern/54841: time(1) reports garbage user and system times again
Date: Thu, 9 Jan 2020 10:55:09 +0200

 This appears to be a long-standing bug, so it's likely also in -9.
 I tested a build from source date 2017.02.23.08.22.20:

   # cd /usr/tests/fs/vfs && time atf-run t_vnops >log
          54.00 real      2334.64 user       466.80 sys

 To use use 2334 seconds of user time in 54 seconds of real time,
 the machine would need to have at least 43 CPUs, but it only has 8.
 -- 
 Andreas Gustafsson, gson@gson.org

From: Andreas Gustafsson <gson@gson.org>
To: gnats-bugs@netbsd.org
Cc: 
Subject: Re: kern/54841: time(1) reports garbage user and system times again
Date: Thu, 9 Jan 2020 17:45:22 +0200

 I ran some more tests.  The -9 branch is affected, but NetBSD/amd64 is
 not, running on the same hardware as the NetBSD/i386 tests exhibiting
 the problem.
 -- 
 Andreas Gustafsson, gson@gson.org

>Unformatted:

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