Definition: flock	last revised by 127.0.0.1 on Aug 17, 2005 4:13 am

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Objects migrate to and from the disk in groupings called "flocks". The flock is the minimum granularity at which objects are purged from core and restored from disk. A flock consists of exactly one shepherd and an arbitrary number of sheep (as long as the entire flock is guaranteed of fitting in a single snarf? Is this true? Michael? Dean? How can we be confident this condition is satisfied?). A "sheep" (what is the singular?) is simply a "COPY(X):" object which needn't be at all cognizant of the disk. The single shepherd in a flock is "representative" of the flock as a whole--the only inter-flock pointers are to shepherds.

This means that the only on-disk pointers to a sheep must be from objects within the same flock as this sheep. If a sheep is an EQObject there is no problem, because a hash table that points to it must be within the same flockD. Given that hash-indexed structures rehash when being read back in off disk, the flock will always be using valid hashes during its stay in core.

--JohnDougan?