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From: Alfred Perlstein <bright@mu.org>
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To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: svn commit: r244112 - head/sys/kern
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Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org,
 Alfred Perlstein <alfred@freebsd.org>, src-committers@freebsd.org,
 John Baldwin <jhb@freebsd.org>
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On 12/12/12 2:15 PM, Adrian Chadd wrote:
> On 12 December 2012 13:58, John Baldwin <jhb@freebsd.org> wrote:
>
>
>> (Note that the primary reason I know for people not running with INVARIANTS
>> enabled is not that they don't want panics, but that they don't want the
>> performance hit.)
> Well, it would be nice to be able to enable invariants on some
> shipping "debug" versions of images in order to gather more data
> without crashing the kernel.
Yes, two of my employers were more of "we want to get more debug 
metrics, we have the spare cycles, but we can't deal with superfluous 
panics".

It also allows us "non-architects" to slip in a debug image when we have 
spare cpu without getting yelled at for "crashing the $foo".


-Alfred