Re: Workaround for wrapping loadaverage

From: Nick Piggin
Date: Wed Nov 10 2004 - 02:11:03 EST


Herbert Poetzl wrote:
On Tue, Nov 09, 2004 at 01:43:35AM +0100, Patrick Mau wrote:


We re-calculate the load every 5 seconds. I think it would be OK to
use more bits/registers, it's not that frequently called.


hmm ...

do_timer() -> update_times() -> calc_load()

so not exactly every 5 seconds ...


calc_load() -> messing with LOAD_FREQ -> once every 5 seconds, no?

I think doing 32/32 bit calculations would be fine.

but I agree that a higher resolution would be a good
idea ... also doing the calculation when the number
of running/uninterruptible processes has changed would
be a good idea ...


Apart from the problem Con pointed out, you'd need a fancier algorithm
to calculate load because your interval isn't going to be fixed, so you
need to factor that in when calculating the area under the 'curve'
(loadavg).

I think the good 'ol 5 seconds should be alright.
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