Methods and mechanisms for proactive memory management

• US 8,032,723 B2
• Filed: 04/13/2010
• Issued: 10/04/2011
• Est. Priority Date: 10/04/2002
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Iyigun, Mehmet, Sechrest, Stuart, Fortin, Michael R., Ergan, Cenk
• Primary Examiner(s): Thai; Tuan V.
• Application Number:
  US12/759,526
• Publication Number:
  US 20100199063A1
• Time in Patent Office: 539 Days
• Field of Search: 711/100, 711/117, 711/118, 711/137, 711/154, 711/158, 711/204
• US Class Current: 711/158
• CPC Class Codes: G06F 12/121 using replacement algorithms
• CPC Class Codes: G06F 12/122 of the least frequently used [LFU] type, e.g. with individual count value

Abstract

A proactive, resilient and self-tuning memory management system and method that result in actual and perceived performance improvements in memory management, by loading and maintaining data that is likely to be needed into memory, before the data is actually needed. The system includes mechanisms directed towards historical memory usage monitoring, memory usage analysis, refreshing memory with highly-valued (e.g., highly utilized) pages, I/O pre-fetching efficiency, and aggressive disk management. Based on the memory usage information, pages are prioritized with relative values, and mechanisms work to pre-fetch and/or maintain the more valuable pages in memory. Pages are pre-fetched and maintained in a prioritized standby page set that includes a number of subsets, by which more valuable pages remain in memory over less valuable pages. Valuable data that is paged out may be automatically brought back, in a resilient manner. Benefits include significantly reducing or even eliminating disk I/O due to memory page faults.

Claims

1. A computer-readable storage medium having stored thereon computer-executable instructions, which when executed perform steps, comprising:

capturing rich information on memory page use, the rich information comprising at least one of pattern, frequency, context and grouping data for the memory pages;

persisting the rich information;

associating a priority value with each memory page for which rich information was captured, wherein the priority value is based on the page'"'"'s usage; and

using the rich information to pre-fetch pages into a memory according to each page'"'"'s associated priority value, prior to an actual demand for the pages.

2. The computer-readable storage medium of claim 1, wherein capturing the rich information comprises sampling actual page usage.

3. The computer-readable storage medium of claim 1, wherein capturing the rich information comprises tracing actual page usage.

4. The computer program product of claim 1, wherein the priority value is based on both the page'"'"'s usage and the page'"'"'s corresponding I/O transfer expense, wherein the I/O transfer expense indicates the potential future cost of loading the page into memory if the page is unloaded onto disk.

5. At a computer system including at least one processor and a memory, in a computer networking environment including a plurality of computing systems, a computer-implemented method comprising:

capturing rich information on memory page use, the rich information comprising at least one of pattern, frequency, context and grouping data for the memory pages;

persisting the rich information;

associating a priority value with each memory page for which rich information was captured, wherein the priority value is based on the page'"'"'s usage; and

using the rich information to pre-fetch pages into a memory according to each page'"'"'s associated priority value, prior to an actual demand for the pages.

6. The method of claim 5, wherein capturing the rich information comprises sampling actual page usage.

7. The method of claim 5, wherein capturing the rich information comprises tracing actual page usage.

8. The method of claim 5, wherein the priority value is based on both the page'"'"'s usage and the page'"'"'s corresponding I/O transfer expense, wherein the I/O transfer expense indicates the potential future cost of loading the page into memory if the page is unloaded onto disk.

9. A computer system comprising the following:

one or more processors;

system memory;

one or more computer-readable storage media having stored thereon computer-executable instructions that, when executed by the one or more processors, causes the computing system to perform a method comprising the following;

capturing rich information on memory page use, the rich information comprising at least one of pattern, frequency, context and grouping data for the memory pages;

persisting the rich information;

associating a priority value with each memory page for which rich information was captured, wherein the priority value is based on the page'"'"'s usage and based on the page'"'"'s corresponding I/O transfer expense, wherein the I/O transfer expense indicates the potential future cost of loading the page into memory if the page is unloaded onto disk; and

using the rich information to pre-fetch pages into a memory according to each page'"'"'s associated priority value, prior to an actual demand for the pages.

10. The computer system of claim 9, wherein capturing the rich information comprises sampling actual page usage.

11. The computer system of claim 9, wherein capturing the rich information comprises tracing actual page usage.