Re: CPU report in first line of "vmstat 1" is meaningless

In the last episode (Oct 18), Ed Maste said:
> On Mon, Oct 18, 2010 at 01:11:42PM -0500, Dan Nelson wrote:
> > Maybe only blank it out on 32-bit machines?  It's a long, and a 64-bit
> > cp_time value essentially won't roll over (at 1 billion increments per
> > second it will roll over in 500 years; we currently increment 133 times
> > per second, I think).  If the value can be calculated accurately, it
> > should be printed.
> 
> Well, it won't roll over, but it's still different from all following
> lines (in that it effectively shows user/system/idle CPU usage since boot
> on the first line, and a snapshot over the last interval from then on).  I
> think it's still better to avoid printing it in that case.

It is documented to do that, though, and could affect scripts that expect to
see average-since-boot info on the first line.  iostat does the same, btw.

> On a related note I'm not sure if it makes sense to have the same
> behaviour for the first line when an interval is set as when it is
> invoked with no interval.

-- 
	Dan Nelson
	dnelson_at_allantgroup.com