I'm curious as to the external behaviour one would expect to see when taking
a non-disruptive dump.
Would you be able to start the dump and then continue working on your
application while the dump continues?
- Don't laugh - we could do that at Stratus because of the mirrored memory.
In the first cut on a general purpose system, I would expect to be able to
start a dump - the system would freeze
during the dump, and then when complete, the system would be responsive once
more. - and not require a reboot.
The reason I ask this, is that I see you folks poking about the IO_APIC area
, and I think you might be thinking about directing interrupts from all
sources to the one CPU that we want running in order to take the dump. I'm
coming from the other direction thinking that I don't want any interrupts at
all during the whole dump process.
Which is easier? Would one technique produce a better dump than the other?
Is freezing the system for the duration of the dump going to cause dropped
connections? - is that why you want to be servicing interrupts? If you
service interrupts for I/O chances are that you will blur the dump.
Bottom line - I wonder if it is easier to status drive the disk controller
or redirect and then restore interrupt routing on the fly.
I look forward to your views -
Richard
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