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From: Peter Maydell <peter.maydell@linaro.org>
Date: Fri, 2 Dec 2016 09:40:38 +0000
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Subject: Re: [Qemu-devel] Support for using TCG frontend as a library
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To: Liviu Ionescu <ilg@livius.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>, Alessandro Di Federico <ale+qemu@clearmind.me>, qemu-devel <qemu-devel@nongnu.org>

On 1 December 2016 at 19:45, Liviu Ionescu <ilg@livius.net> wrote:
>
>> On 1 Dec 2016, at 21:13, Peter Maydell <peter.maydell@linaro.org> wrote:
>>
>> You need a QCOW2 disk to store the snapshots on, ...
>> Taking savevm snapshots doesn't need any cooperation
>> from the guest OS ..
>> I don't know whether anybody's tested this with M profile:
>
> does your Stellaris board support this?
>
> assuming I fix my devices to save their status and I can correctly
> resume from a given snapshot, I still fail to understand how to
> integrate this feature in the usual debugging workflow.

The most useful approach is that you can set up a complicated
situation (eg "boot my embedded RTOS, start application"),
snapshot at that point, and then you can repeatedly restart
debugging from the snapshot without having to take ages going
through the bootup process each time. (Particularly useful if
you turn on heavyweight tracing which can turn bootup from
"fairly fast" to "incredibly slow".)

thanks
-- PMM