Shared memory in a virtual environment

A computer program product for sharing a physical memory page among a plurality of logical partitions (LPARs) included in a computer, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to perform a method comprising:

• receiving a get-page-ID request that includes an identity of a shared page and an identity of a shared memory region (SMR) that includes the shared page, wherein the SMR is associated with a first LPAR and the get-page-ID request is associated with a second LPAR;
• communicating to the first LPAR a request to identify a physical page in a physical memory of the computer that corresponds to the shared page;
• receiving, in response to the get-page-ID request, a page ID response that comprises an identity of a first logical page that corresponds to the shared page and the physical page;
• communicating to the second LPAR, in response to the page ID response, a first identity of the physical page, wherein the first identity of the physical page is an encrypted page number corresponding to the physical page;
• converting the encrypted page number to a physical page number;
• and
• entering the physical page number into an address translation element, wherein the address translation element is operative to translate the identity of the physical page number to a physical page address of the physical page.

A system for sharing a physical memory page between logical partitions (LPARs), the system comprising:

• a memory;
• and
• a processor communicatively coupled to the memory, wherein the processor is configured to perform a method comprising:
• receiving a get-page-ID request that includes an identity of a shared page and an identity of a shared memory region (SMR) that includes the shared page, wherein the SMR is associated with a first LPAR and the get-page-ID request is associated with a second LPAR;
• communicating to the first LPAR a request to identify a physical page that corresponds to the shared page, the physical page being in a physical memory of a computer that includes the first LPAR;
• receiving, in response to the get-page-ID request, a page ID response that comprises an identity of a first logical page that corresponds to the shared page and the physical page;
• communicating to the second LPAR, in response to the page ID response, a first identity of the physical page, wherein the first identity of the physical page is an encrypted page number corresponding to the physical page;
• converting the encrypted page number to a physical page number;
• and
• entering the physical page number into an address translation element, wherein the address translation element is operative to translate the identity of the physical page number to a physical page address of the physical page.