Memory management techniques

Patent metadata

Field	Value
Publication number	US-10114740-B2
Application number	US-201514880264-A
Country	US
Kind code	B2
Filing date	Oct 11, 2015
Priority date	Sep 12, 2011
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

Memory management techniques that permit an executing process to store content in memory and later retrieve that content from the memory, but that also permit a memory manager to discard that content to address memory pressure. A process executing on a computing device may notify a memory manager of the computing device that first memory space allocated to the process contains first content that is available for discard. If the memory manager detects the computing device is experiencing memory pressure, the memory manager may address the memory pressure by selecting memory space available for discard and discarding the content of the memory space. Before a process reuses content made available for discard, the process may notify the memory manager of the intent to reuse and, in response, receive empty memory and an indication that the content was discarded or receive an indication that the content is still available for use.

First claim

What is claimed is:

1. A computing device, the computing device comprising:
at least one memory and at least one processor, the at least one memory and the at least one processor being respectively configured to store and execute instructions, including instructions for performing operations, the operations including:
allocating space in the at least one memory to a process executing on the computing device;
receiving an instruction from the process that:
data stored in at least a portion of the allocated space is to be discarded,
the data stored in at least the portion of the allocated space is to be retained, or
the data stored in at least the portion of the allocated space is available to be potentially discarded;

retaining or discarding the data based at least in part on the instruction and on memory usage for the computing device, wherein the instruction is based at least in part on whether the process is capable of regenerating the data.

2. The computing device of claim 1 , wherein the operations also include:
receiving the instruction that the data stored in at least the portion of the memory space is available to be potentially discarded;
subsequently receiving a request from the process for the data; and
providing the data to the process.

3. The computing device of claim 1 , wherein the operations also include:
receiving the instruction that the data stored in at least the portion of the memory space is available to be potentially discarded; and
receiving a notification of a priority level for the data stored in at least the portion of the allocated space that is available to be potentially discarded.

4. The computing device of claim 1 , wherein the operations also include:
receiving the instruction that the data stored in at least the portion of the memory space is available to be potentially discarded; and
retaining or discarding the data available to be potentially discarded based at least in part on whether the computing device is to undergo a power state transition.

5. The computing device of claim 1 , wherein:
the process is a graphics driver process; and
the data is a render target.

6. The computing device of claim 1 , wherein the instruction that the data stored in at least the portion of the allocated space is available to be potentially discarded is also an indication that the allocated space is to remain allocated to the process.

7. The computing device of claim 1 , wherein the instruction is based at least in part on a determination that the data will not be used within a threshold period of time.

8. A method of managing memory, the method comprising:
allocating space in at least one memory to a process executing on the computing device;
receiving an indication from the process that the data stored in at least the portion of the allocated space is available to be potentially discarded; and
managing the data available to be potentially discarded based at least in part on the indication and on memory usage for the computing device, wherein the indication is based at least in part on a determination that the data will not be used within a threshold period of time.

9. The method of claim 8 , further comprising:
after receiving the indication, receiving a request from the process for the data; and
providing the data to the process.

10. The method of claim 8 , further comprising:
receiving a notification of a priority level for the data stored in at least the portion of the allocated space that is available to be potentially discarded.

11. The method of claim 8 , wherein managing the data available to be potentially discarded includes:
retaining or discarding the data available to be potentially discarded based at least in part on whether the computing device is to undergo a power state transition.

12. The method of claim 8 , wherein:
the process is a graphics driver process; and
the data available to be potentially discarded is video data.

13. The method of claim 8 , wherein the indication that the data stored in at least the portion of the allocated space is available to be potentially discarded is also an indication that the allocated space is to remain allocated to the process.

14. The method of claim 8 , wherein the indication is based at least in part on a whether the process can regenerate the data.

15. A computing device, comprising:
at least memory device; and
at least one processor, wherein the at least one memory device and the at least one processor respectively store and execute instructions, including instructions that cause the at least one processor to manage memory allocated to one or more processes executing on the computing device, the management of the memory comprising:
receiving an indication that a first allocated memory space contains first content that is available for discard;
receiving an indication that a second allocated memory space contains second content that is available for discard;
subsequently receiving an indication of a shortage of memory space available for use by the computing device;
selecting, based at least in part on a determination that the data will not be used within a threshold period of time, from amongst the first content and the second content, which content is to be discarded; and
discarding the selecting content.

16. The computing device of claim 15 , wherein the selecting of which content is to be discarded is based at least in part on a time the first or second content was indicated as available for discard or an indicated priority level of the first or second content.

17. The computing device of claim 15 , wherein the management of the memory also includes receiving indications of priority levels for the first content and the second content, and wherein the selecting of which content is to be discarded is based at least in part the indicated priority level of the first content and on the indicated priority level of the second content.

18. The computing device of claim 15 , wherein discarding the selected content includes allowing the selected content to be overwritten.

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Pronovost Steve
• Abernethy Maxwell
• Balaz Rudolph
• Chitre Ameet

Classifications

• G06F12/0891

  using clearing, invalidating or resetting means · CPC title

• G06F2212/657

  Virtual address space management · CPC title

• G09G5/001

  Arbitration of resources in a display system, e.g. control of access to frame buffer by video controller and/or main processor · CPC title

• G06F12/0638

  Combination of memories, e.g. ROM and RAM such as to permit replacement or supplementing of words in one module by words in another module (address formation of the next microinstruction G06F9/26; masking faults in memories by using spares or by reconfiguring G11C29/70) · CPC title

• G06T1/60

  Memory management · CPC title