System and method for migrating data between memories

A system for migrating data from one location to another, said system comprising:

• a first set of memory locations, said memory locations holding data accessible by at least one accessing device;
• a second set of memory locations, said memory locations available for holding data accessible by said at least one accessing device;
• means for accessing selective locations within both said first and said second memory locations, said accessing preventing access to said selective memory locations by any other devices;
• a transfer path for moving data from selected locations within said first set of memory locations to selected locations within said second set of memory locations;
• and
• means operative when said data is moved into said second set of memory locations for removing said preventing of said access.

A computer comprising:

• an operating system for controlling said computer;
• at least one memory having locations therein at which data is stored;
• at least one accessing system for obtaining data from said locations within said one or more memories, the manner of said accessing controlled in part by said operating system in accordance with a data storage map;
• a system for selecting locations within said at least one memory between which data is to be migrated, said selecting system operable for inhibiting accessing to both to and from locations associated with said data to be migrated while data is in the process of migrating between said to and from locations;
• said system further operable after said data has migrated for allowing an accessing system to access data locations in a memory from which data has migrated and to redirect, under control of said operating system and said at least one memory, the location to which said data has migrated;
• and
• said system further operable after all data which is to be migrated has migrated for causing said operating system to modify said such that new data accessing instructions are directed to the memory location to which said data has migrated and not to the previous location of said data.

A method of operating a computer, said method comprising:

• enabling an operating system within said computer to control functions of said computer, one such function being the accessing of data from locations within a first memory, said accessing in accordance with a map of data;
• adding, while said computer is in operation, an additional memory to said computer, said additional memory having locations therein where data can be stored;
• migrating while said computer is in operation, data from said first memory to said additional memory, said migrating occurring in stages, each stage containing portions of data from said first memory;
• and
• while said stages are being migrated, enabling said first memory to redirect to said additional memory any data accesses directed to portions of data which have already migrated and when all of said stages are complete, changing said map so that subsequent data accesses are directed to said additional memory.

A method for migrating data from one location to another, said method comprising:

• establishing a new memory location under control of a specific memory accessing device, said new memory location being where data which is being migrated from a first memory location is to reside;
• selecting under control of said specific accessing device, a certain portion of data resident at said first memory location;
• obtaining, under control of said specific accessing device, the most recent version of said certain data from said first memory location, said obtaining causing subsequent accesses by unrelated accessing devices to be redirected back to said unrelated accessing devices for re-issuance to said new memory location;
• forwarding, under control of said specific accessing device, the said obtained certain data to said new memory location;
• and
• if said new memory location receives said redirected access from said unrelated accessing devices before receiving said forwarded certain data, then said redirected accesses are prevented until said forwarded data is written to the said new memory location.

A method for migrating data from one location to another, said method comprising:

• establishing a new memory location under control of a specific memory accessing device, said new memory location being where data which is being migrated from a first memory location is to reside;
• said specific accessing device taking control of a certain portion of data resident at said first memory location, said control preventing said certain data from being accessed by any device other than said specific accessing device;
• obtaining, under control of said specific accessing device, the most recent version of said certain data from said first memory location;
• forwarding, under control of said specific accessing device, the said obtained certain data to said new memory location;
• and
• after said certain data is received and written into said new memory location, marking said certain data as being gone from said first memory location such that attempts to access said certain data at said first memory location from a specific unrelated accessing device will be redirected back to said unrelated accessing device for redirection to said new memory location.