Re: Workaround for wrapping loadaverage

[Patrick Mau <mau@oscar.ping.de>]

On Mon, Nov 08, 2004 at 01:27:07AM -0800, Andrew Morton wrote:
> Patrick Mau <mau@oscar.ping.de> wrote:
> >
> >  We can only account for 1024 runnable processes, since we have 22 bits
> >  precision, I would like to suggest a patch to calc_load in kernel/timer.c
> 
> It's better than wrapping to zero...
> 
> Why do we need 11 bits after the binary point?

I tried various other combinations, the most interesting alternative was
8 bits precision. The exponential values would be:

1 / e (5/60) * 256
235.53

1 / e (5/300) * 256
251.76

1 / e (5/900) * 256
254.58

If you would use 236, 252 and 255 the last to load calculations would
get optimized into register shifts during calculation. The precision
would be bad, but I personally don't mind loosing the fraction.

Best regards,
Patrick