[coyotos-dev] Safe states for userspace

[Pierre THIERRY]

As I was presenting my paper on persistence in a workshop of ECOOP, the
mention of orthogonal persistence triggered a question about the
relation between checkpointing and userspace applications: the
checkpoint is guaranteed to save only consistent states of the system,
but is there a way for an application to declare when it has reached
such a consistent state itself?

Else, what would happen when the application is in a inconsistent state,
the system is checkpointed, shut down, and restarted?

The problem is, I suppose in some cases it could lead to a crash of the
application. With non orthogonal persistence, you would still have the
serialized state at hand, be able to restart the application, inspect
what goes wrong, and maybe try to tweak the state to get it to some
consistent state.

But in Coyotos, if the application crashes because of an inconsistent
state, won't its storage be reclaimed? In which case, well, game is
over.

Transactionally,
Pierre
-- 
nowhere.man at levallois.eu.org
OpenPGP 0xD9D50D8A
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