On Tue, Oct 19, 2010 at 08:54:38AM -0400, John Baldwin wrote:
quoted text
> On Monday, October 18, 2010 3:30:11 pm Ed Maste wrote:
> > 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.
> 
> All of the first line is that way though.  To do this "right" you'd need to
> blank out the entire first line.
> 
> vm_stat and iostat on OS X have the current FreeBSD behavior (instant first
> line that summarizes all activity since uptime), so I'd be inclined to just
> leave the existing behavior.

I'd be very happy if all vmstat and iostat would get a command line
switch to suppress the "summary since last reboot" line.
This information may be useful for some cases but in other cases, like
creating performance data for monitoring systems like Icinga / Nagios
one has to remove the first line(s) manually.