CDS, replace ArchiveRelocationMode?

[Thomas Stüfe]

Hi,

A small idea. I wonder whether we could reduce the complexity of CDS
reservation a bit and at the same time make testing more realistic by
replacing ArchiveRelocationMode with a test switch that, prior to any
initialization, populates the address space with "inconvenient"
reservations. Either targeted to some predefined areas or scattershot for
random tests.

A function like "scattershot_into_range(address, len)" could be called even
between reserving the whole range and mapping the individual ranges, to
mimic reservation failures where "oops someone was faster than you".

Such a feature could be reused in a number of places, and we could remove
the ArchiveRelocationMode switch and its handling. What do you think?

Cheers, Thomas