Browse Prior Art Database

Promote on Access

IP.com Disclosure Number: IPCOM000117593D
Original Publication Date: 1996-Apr-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 4 page(s) / 140K

Publishing Venue

IBM

Related People

Bowers, DR: AUTHOR [+3]

Abstract

A program is disclosed that provides on an individual data item basis a policy-based temporary promotion of the data item to a higher level of a multi-level storage heirarchy in response to an unplanned ad-hoc reference to the data. For each individual data item, policies will indicate whether the data item should even be considered for promotion and, if the data item is to be promoted, again policies are used to determine the level to which the promotion is to occur as well as the duration of the promotion. The temporary promotion makes the data item more readily accessible on anticipated subsequent references to the data item for the duration of the promotion.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 44% of the total text.

Promote on Access

      A program is disclosed that provides on an individual data item
basis a policy-based temporary promotion of the data item to a higher
level of a multi-level storage heirarchy in response to an unplanned
ad-hoc reference to the data.  For each individual data item,
policies will indicate whether the data item should even be
considered for promotion and, if the data item is to be promoted,
again policies are used to determine the level to which the promotion
is to occur as well  as the duration of the promotion.  The temporary
promotion makes the data  item more readily accessible on anticipated
subsequent references to the  data item for the duration of the
promotion.

      The foundation for the disclosed program is a storage heirarchy
management system.  A number of elements are implied in any given
storage heirarchy management system, however only those aspects of a
subset of those elements that are related to the disclosed program
are described or referenced herein.  Storage policies provide generic
specifications as to the level of the storage heirarchy into which a
data item is to be placed.  Management policies provide
specifications as to the duration for which a data item is to reside
at a given level  of the storage heirarchy.  The duration may include
specifications such  as 'time since the data was stored', 'time since
the data was last retrieved', as well as periodic events.  A given
data item may have planned policy assignments which allow the data
item to undergo a storage  heirarchy transition that may imply
movement up or down a multi-level storage heirarchy.  The storage
heirarchy management system acts on the assigned policies and
includes a mechanism for the actual policy assignment.  The mechanism
for policy assignment allows association of  policies with a data
item for a number of contexts or environments in which the data item
may be presented for policy assignment.  These environments may
include 'store' (i.e., storage of a data item into the  storage
heirarchy), 'change policies' (i.e., an external request to change
the policies associated with a data item), and automatic
policy-driven 'storage heirarchy transition' (i.e., an internal
request from the storage heirarchy management system to change the
policies associated with a data item).

      The disclosed program provides extensions to the management
policy and to the storage heirarchy management system.  The
management policy is extended to include the specification as to
whether promotion for a data item is to be considered.  The storage
heirarchy management system is extended to include a new policy
assignment environment of 'retrieve' (i.e., an external reference to
the data item which may imply a request to change the policies
associated with the data item) and acting on the policy assignments
to a data item in the 'retrieve' environment.

As illustrated in Fig. 1.:
  1.  Within the storage heirarchy...