A method to assign a premigration pseudotime attribute and a stubbing pseudotime
attribute to a logical volume. The method defines a plurality of host requests,
and associates with each host request a pseudotime range. The method further maintains
a logical volume in a first information storage medium at a first time, and determines
if a user provides a host request for that logical volume. If a user provides a
host request for that logical volume, then the method assigns to the logical volume
a premigration pseudotime attribute, and a stubbing pseudotime attribute, comprising
a time within the pseudotime range associated with the host request. If, on the
other hand, a user does not provide a host request for the logical volume, then
the method assigns to that logical volume the first time as said premigration pseudotime
attribute, and said first time as said stubbing pseudotime attribute. The method
saves the assigned premigration pseudotime attribute and the assigned stubbing
pseudotime attribute for later use.
