RE: Reclaiming Storage...Re-booting Regularly

Sue,

I would be interested in your results and regret I don't currently have
a system available to test with both *ALL and *MIN in the IPL
attributes.

A key assumption in the advice I gave was that the hardware diagnostics
were performed in a matter of minutes, as opposed to tens of minutes.
I'm basing this on many years of watching SRC codes during IPL's.  Not
exactly an empirical comparison, but it is of some value.  I would
expect differences related to the size and complexity of the hardware
configuration.

My impression is that a few years back, IBM felt a need to address the
speed of IPL's as a competitive marketing imperative.  It was an
extremely long process at that time.  I remember the technical marketing
documentation highlighted the decrease in IPL times.  So by stripping
out anything which could be considered optional, regardless of its
actual duration, they did achieve dramatic reductions in boot time.  I'm
sure there was also some streamlining of code, performing multiple tasks
concurrently, and moving some tasks into the OS to be performed after
the system was available.  This is all good stuff and IBM was, I
believe, successful in their task.

I would be interested in having my assumption tested, I don't mind being
wrong.  (Actually I do but I can live with it :-))

Regards,
and Thanks,
Andy Nolen-Parkhouse



> On Behalf Of Sue Baker
> Subject: RE: Reclaiming Storage...Re-booting Regularly
>
> "Andy Nolen-Parkhouse"
>
> Andy, the problem I see with changing the default setting is when
> your under emergency conditions, you have to remember to change
> things.  Regardless of your 24x7 needs, consider the situation
> where all power is lost and your UPS fails and it occurs during
> the normal business day.  With the defaults set to always perform
> full diagnostics, you'd have that amount of time plus abnormal
> IPL time.  Because this doesn't happen often, if ever, you could
> forget to make the change via the control panel to use
> abbreviated diagnostics.  This in turn could create a huge
> problem for you and your business.  The key question in all of
> this is "how much longer is *ALL than *MIN?"  Of course, we
> really don't know for sure, but I tend to plan for the disaster
> and be pleasantly surprised when things work out better.  Or I
> don't need the disaster plans at all :)