International Business Machines Corporation

Jaime A Jaloma

Mark D Rogers

Arnold Flores

Gaurav Batra

During a memory reallocation process, it is determined that a set of memory pages being reallocated are each enabled for a Direct Memory Access (DMA) operation. Prior to writing initial data to the set of memory pages, a pre-access delay is performed concurrently for each memory page in the set of memory pages.

Minimizing delay while migrating direct memory access (DMA) mapped pages

Scalable virtual memory metadata management comprising a plurality of pre-instantiated VM metadata containers representing the entire amount of real physical memory available to a computing system, with additional instantiated VM metadata containers created as needed. Individual and/or groups of VM metadata containers are assigned to metadata container groups, wherein each container group is controlled by an acquired lock assigned to the VM metadata container groups. Virtual memory metadata is managed using a 'least used' technique. In response to allocation requests, the allocator scans the container groups/VM containers and fulfills memory object metadata allocation to the least used VM metadata container of the least used container group, filling the individual VM metadata containers and/or the container groups at a nearly equal rate.

Scalable virtual memory metadata management

A method of operating a virtual memory manager (VMM) in a computing system is provided. The method includes receiving a boot-up instruction, determining an amount of available configurable memory, determining a system logical memory block (LMB) size and selecting a memory stripe size for memory stripes respectively associated with LMBs provided within the available configurable memory. The selecting of the memory stripe size for the memory stripes is based in part on the determined amounts of the available configurable memory and the system LMB size.

Memory stripe with selectable size

A computing system is provided and includes first and second computing resources defined, during system initialization, as first kernel threads and a second kernel thread with which the first kernel threads are operably associated, a memory manager and a re-prioritization controller. The memory manager is configured to handle a portion of pending input/output (I/O) operations at an interrupt level and to offload a remainder of the pending I/O operations to the first kernel threads according to an offload condition whereby the offloaded I/O operations are queued according to a first scheme. The re-prioritization controller is configured to transfer a portion of the offloaded I/O operations from the first kernel threads to the second kernel thread according to a transfer condition whereby the transferred I/O operations are re-prioritized according to a second scheme.

Growing community of inventors

Austin, TX, United States of America

Jaime A Jaloma