Partition mobility for partitions with extended code

1. A computer program product for managing migration of partitions, said computer program product comprising:

a computer readable storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising:

obtaining, by an optimizer executing in a processor, an indication that a partition included in memory of a first host system, the partition executing on the first host system and executing an application, of a plurality of applications of the partition, using one or more extended mode features, is to be migrated to a second host system, different from the first host system, in which at least one extended mode feature of the one or more extended features is unsupported; and

removing, based on obtaining the indication, at least a portion of code of the application to facilitate migration of the partition to the second host system in which at least one extended mode feature is unsupported, wherein the removing comprises:

determining whether the application is currently executing optimized code of the application or unoptimized code of the application; and

based on determining the application is currently executing optimized code of the application:

checking whether the optimized code is currently executing code that is unsupported by the second host system to which the partition is being migrated; and

based on the checking indicating the optimized code is currently executing code that is unsupported by the second host system, obtaining state of the unoptimized code, and based on obtaining the state, removing the at least a portion of the code.

2. The computer program product of claim 1 , wherein the one or more extended mode features comprise a feature at an instruction set architecture level different from an instruction set architecture level of the application.

3. The computer program product of claim 1 , wherein the application comprises optimized code, the optimized code including the one or more extended mode features, and wherein the removing further comprises removing the optimized code.

4. The computer program product of claim 1 , wherein the application comprises optimized code, the optimized code including the one or more extended mode features, and wherein the removing further comprises removing a portion of the optimized code, the portion of the optimized code being unsupported by the second host system.

5. The computer program product of claim 1 , wherein the method further comprises reporting completion of the removing the at least a portion of the code, and based on reporting within a predefined time window, migration of the partition continues.

6. The computer program product of claim 1 , wherein the obtaining comprises obtaining the indication from a component of the computing environment, and based on the component determining the optimizer has not reported completion of the removing the at least a portion of the code within a predefined time window, the application is cancelled or terminated.

7. The computer program product of claim 1 , wherein the removing further comprises:

based on determining the application is currently executing unoptimized code of the application:

removing the at least a portion of the code; and

reporting that the at least a portion of the code has been removed, wherein the application continues to execute.

8. The computer program product of claim 1 , wherein the removing further comprises:

based on determining the application is currently executing optimized code of the application:

checking whether the optimized code is currently executing code that is supported by the second host system to which the partition is being migrated; and

based on the checking indicating the optimized code is currently executing code that is supported by the second host system, removing the at least a portion of the code, and reporting that the at least a portion of the code is removed, wherein the application continues to execute.

9. The computer program product of claim 1 , wherein the application continues executing based on the obtained state.

10. The computer program product of claim 1 , wherein the partition comprises a logical partition or virtual machine.

11. A computer system for managing migration of partitions, said computer system comprising:

a memory; and

a processor in communications with the memory, wherein the computer system is configured to perform a method, said method comprising:

obtaining, by an optimizer executing in the processor, an indication that a partition included in memory of a first host system, the partition executing on the first host system and executing an application, of a plurality of applications of the partition, using one or more extended mode features, is to be migrated to a second host system, different from the first host system, in which at least one extended mode feature of the one or more extended features is unsupported; and

removing, based on obtaining the indication, at least a portion of code of the application to facilitate migration of the partition to the second host system in which at least one extended mode feature is unsupported, wherein the removing comprises:

determining whether the application is currently executing optimized code of the application or unoptimized code of the application; and

based on determining the application is currently executing optimized code of the application:

checking whether the optimized code is currently executing code that is unsupported by the second host system to which the partition is being migrated; and

based on the checking indicating the optimized code is currently executing code that is unsupported by the second host system, obtaining state of the unoptimized code, and based on obtaining the state, removing the at least a portion of the code.

12. The computer system of claim 11 , wherein the application comprises optimized code, the optimized code including the one or more extended mode features, and wherein the removing further comprises removing the optimized code.

13. The computer system of claim 11 , wherein the application comprises optimized code, the optimized code including the one or more extended mode features, and wherein the removing further comprises removing a portion of the optimized code, the portion of the optimized code being unsupported by the second host system.

14. The computer system of claim 11 , wherein the obtaining comprises obtaining the indication from a component of the computing environment, and based on the component determining the optimizer has not reported completion of the removing the at least a portion of the code within a predefined time window, the application is cancelled or terminated.

15. The computer system of claim 11 , wherein the removing further comprises:

based on determining the application is currently executing unoptimized code of the application:

removing the at least a portion of the code; and

reporting that the at least a portion of the code has been removed, wherein the application continues to execute.

16. The computer system of claim 11 , wherein the removing further comprises:

based on determining the application is currently executing optimized code of the application:

checking whether the optimized code is currently executing code that is supported by the second host system to which the partition is being migrated; and

based on the checking indicating the optimized code is currently executing code that is supported by the second host system, removing the at least a portion of the code, and reporting that the at least a portion of the code is removed, wherein the application continues to execute.

17. The computer system of claim 11 , wherein the partition comprises a logical partition or a virtual machine.