Live operating system update mechanisms

1. A computer program product comprising a non-transitory computer readable medium having a computer readable program stored therein, wherein the computer readable program, when executed on a computing device, causes the computing device to:

receive an update to an operating system;

clone an original root volume group associated with an operating system instance executing in a first logical partition of the computing device to generate a cloned root volume group for booting a second logical partition of the computing device;

mirror the original root volume group associated with the operating system instance executing in the first logical partition of the computing device to generate a mirrored root volume group in the first logical partition, wherein modifications to the original root volume group are mirrored to the mirrored root volume group;

apply the update to the cloned root volume group to generate an updated and cloned root volume group;

boot the second logical partition of the data processing system using the updated and cloned root volume group without shutting down and restarting the computing device;

import the mirrored root volume group into the booted second logical partition; and

migrate application instances to the second logical partition by restarting the application instances in the booted second logical partition using the mirrored root volume group.

2. The computer program product of claim 1 , wherein the computer readable program further causes the computing device to:

freeze, prior to importing the mirrored root volume group into the booted second logical partition, application instances running in the first logical partition until the application instances are restarted in the second logical partition, wherein freezing application instances comprises preventing modifications to a root file system of the mirrored root volume group by the application instances while the application instances are frozen.

3. The computer program product of claim 1 , wherein the computer readable program further causes the computing device to:

split, prior to importing the mirrored root volume group into the booted second logical partition, the mirrored root volume group from the original root volume group such that modifications to the original root volume group are not mirrored to the mirrored root volume group.

4. The computer program product of claim 1 , wherein the computer readable program further causes the computing device to:

apply the update to the mirrored root volume group imported into the booted Second logical partition after importing the mirrored root volume group into the booted second logical partition.

5. The computer program product of claim 4 , wherein the computer readable program further causes the computing device to apply the update to the mirrored root volume group prior to completion of the migration of the application instances to the booted second logical partition.

6. The computer program product of claim 4 , wherein the computer readable program further causes the computing device to apply the update to the mirrored root volume group after completion of the migration of the application instances to the booted second logical partition.

7. The computer program product of claim 1 , wherein the mirroring operation is performed in parallel with the cloning operation.

8. The computer program product of claim 1 , wherein the computer readable program further causes the computing device to:

store a first data structure specifying a set of base services that cannot be migrated from the first logical partition to the second logical partition; and

identify a set of migratable services that can be migrated from the first logical partition to the second logical partition, wherein booting the second logical partition comprises migrating the identified set of migratable services from the first logical partition to the second logical partition, wherein the set of migratable services is customized to boot the second logical partition using a minimal set of services necessary to establish a network connection with the first logical partition and receive migrated application instances.

9. The computer program product of claim 8 , wherein the computer readable program further causes the computing device to:

maintain the first logical partition operational with the set of base services specified in the first data structure executing in the first logical partition until migration of the application instances and application data to the booted second logical partition is complete.

10. A data processing system comprising:

a processor; and

a memory coupled to the processor, wherein the memory comprises instructions which, when executed by the processor, cause the processor to:

receive an update to an operating system;

clone an original root volume group associated with an operating system instance executing in a first logical partition of the data processing system to generate a cloned root volume group for booting a second logical partition of the data processing system;

mirror the original root volume group associated with an operating system instance executing in a first logical partition of the data processing system to generate a mirrored root volume group in the first logical partition, wherein modifications to the original root volume group are mirrored to the mirrored root volume group;

apply the update to the cloned root volume group to generate an updated and cloned root volume group;

boot the second logical partition of the data processing system using the updated and cloned root volume group without shutting down and restarting the data processing system;

import the mirrored root volume group into the booted second logical partition; and

migrate application instances to the booted second logical partition by restarting the application instances in the booted second logical partition using the mirrored root volume group.