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Re: regression (crash) in sysmon/acpiacad

On Thu, 4 Feb 2010, Matthias Drochner wrote: said:
Since the charge value was not updating, it  might be that the ACPI
Notify isn't working here.

For the critical shutdown, a call to _BTP might help.
But anyway, from my limited experience with process control
("SCADA") systems, it makes sense to maintain a timestamp
for the last data value read (or delivered by asynchronous
notification) and force a fresh read if it is older than
a limit defined by the provider (and possibly overridden
by the consumer).

I was thinking more along the lines of disabling the "manual"
refresh only after a Notify actually came in.  But checking the
age of the last Notify/update might be better.

We already have a Poll timer, but it is only 30 seconds.  I don't
know how ofter we should expect a Notify event, but I bet that it
doesn't happen every 30 sec!

All this needs a bit more thinking ...

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