checkpoint/restart

[Peter Fay]

Does anyone out there have any experience using checkpoint/restart as a user
or coding it in the O.S.? I know Unicos claims to have that facility and have
read the Unicos manual, but I know little about how it or any other Unix
checkpoint is implemented.

What are the issues that come up when putting this into the O.S. (esp. Unix)?
What capabilities do users really want and need?
Does checkpoint save only files that are currently opened or all that have
been accessed in the program to date?
What is a Unicos process "category" and how does that relate to pid and
chkpnt?
Is there a runtime environment that does all the chkpnt/restart for the
applications or is it a roll-your-own situation?

-pete fay
{harvard.harvard.edu!ksr!fay}