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From: John Baldwin <jhb@freebsd.org>
To: "current@freebsd.org" <current@freebsd.org>
Subject: Change top's notion of idle processes / threads
Date: Fri, 23 May 2014 16:05:26 -0400
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Right now, when top is set to not display idle processes or threads, it only 
displays processes or threads that are currently in a runnable state or have a 
non-zero %cpu.  However, our %cpu is quite imprecise.  I have patch to change 
top to instead compare the thread or processes runtime (ki_runtime in 
kinfo_proc) against the runtime of the thread or process the last time data 
was fetched.  In essence, top will consider any thread that has run on a CPU 
since the last update as non-idle.  The end result is that mostly-idle threads 
and processes will now be visible in top's idle display.  Personally, I find 
this more useful (and find the current implementation completely useless).  
The patch is at http://people.freebsd.org/~jhb/patches/top_idle.patch

Comments?

-- 
John Baldwin