Re: architecture diagram

[Douglas Thain <thain@cs.wisc.edu>]

> How do other people with existing CPR systems determine where checkpoints
> should be written to?

In Condor, the decision of where to send a checkpoint is delegated to the
"shadow" process.  In order to make its decision, the shadow consults the
list of the checkpoint servers available from the matchmaker, as well as any
"suggested" checkpoint server mentioned by the execution site.  The user can
exert some control over this decision, for example, by permitting or
forbidding the use of the execution site's recommendation.

Generally speaking, the shadow process is consulted for all questions of
what resources to access, such as what files to open, what executable to
use, and so forth.  Not all of the shadow's decisions are currently
*clever*, but there is always one place to go for such decisions...