Live operating system update mechanisms

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

receive an update to an operating system;

clone a 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;

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

identify a set of migratable services that can be migrated from the first logical partition to the second logical partition based on the first data structure;

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, wherein booting the second logical partition comprises migrating the identified set of migratable services from the first logical partition to the second logical partition, and 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; and

migrate application instances and application data to the booted second logical partition, wherein base processes specified in the first data structure are executed as child processes of an initialization process or other base processes, child processes of a base process are also considered base processes, and base processes specified in the first data structure do not share resources with non-base processes.

2. The computer program product of claim 1 , 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 second logical partition is complete.

3. The computer program product of claim 2 , wherein user space processes continue to access application instances executing on the first logical partition while the update is applied to the cloned root volume group and the second logical partition is booted.

4. The computer program product of claim 1 , wherein the updated and cloned root volume group comprises at least one of an operating system image corresponding to the root volume group of the first logical partition, which has been updated in accordance with the received update, or a shared library corresponding to the root volume group of the first logical partition, which has been updated in accordance with the received update.

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

in response to completing migration of the application instances and application data to the second logical partition, deactivate the first logical partition and freeing resources associated with the first logical partition for reuse.

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

configure a network connection of the second logical partition to utilize a same hostname and network address as a corresponding network connection of the first logical partition.

7. The computer program product of claim 1 , wherein the application data is migrated from the first logical partition to the second logical partition asynchronously.

8. An apparatus 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:

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;

receive an update to an operating system;

clone a 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;

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

identify a set of migratable services that can be migrated from the first logical partition to the second logical partition based on the first data structure;

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, wherein booting the second logical partition comprises migrating the identified set of migratable services from the first logical partition to the second logical partition, and 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; and

migrate application instances and application data to the booted second logical partition, wherein base processes specified in the first data structure are executed as child processes of an initialization process or other base processes, child processes of a base process are also considered base processes, and base processes specified in the first data structure do not share resources with non-base processes.

9. The apparatus of claim 8 , wherein the instructions further cause the processor 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 second logical partition is complete.

10. The apparatus of claim 9 , wherein user space processes continue to access application instances executing on the first logical partition while the update is applied to the cloned root volume group and the second, logical partition is booted.

11. The apparatus of claim 8 , wherein the updated and cloned root volume group comprises at least one of an operating system image corresponding to the root volume group of the first logical partition, which has been updated in accordance with the received update, or a shared library corresponding to the root volume group of the first logical partition, which has been updated in accordance with the received update.

12. The apparatus of claim 8 , wherein the instructions further cause the processor to:

in response to completing migration of the application instances and application data to the second logical partition, deactivate the first logical partition and freeing resources associated with the first logical partition for reuse.

13. The apparatus of claim 8 , wherein the instructions further cause the processor to:

configure a network connection of the second logical partition to utilize a same hostname and network address as a corresponding network connection of the first logical partition.

14. The apparatus of claim 8 , wherein the application data is migrated from the first logical partition to the second logical partition asynchronously.

15. The apparatus of claim 8 , wherein the instructions further cause the processor to migrate application instances and application data to the second logical partition at least by recreating, in the second logical partition, each application instance of an application using a same process identifier and process tree as associated with an original instance of the application executing in association with the operating system instance in the first logical partition of the data processing system.

16. The computer program product of claim 1 , wherein the computer readable program further causes the computing device to migrate application instances and application data to the second logical partition at least by recreating, in the second logical partition, each application instance of an application using a same process identifier and process tree as associated with an original instance of the application executing in association with the operating system instance in the first logical partition of the data processing system.