US 7,752,417 B2 · Dynamic selection of memory virtualization techniques

Abstract

A computer system may be configured to dynamically select a memory virtualization and corresponding virtual-to-physical address translation technique during execution of an application and to dynamically employ the selected technique in place of a current technique without re-initializing the application. The computer system may be configured to determine that a current address translation technique incurs a high overhead for the application's current workload and may be configured to select a different technique dependent on various performance criteria and/or a user policy. Dynamically employing the selected technique may include reorganizing a memory, reorganizing a translation table, allocating a different block of memory to the application, changing a page or segment size, or moving to or from a page-based, segment-based, or function-based address translation technique. A selected translation technique may be dynamically employed for the application independent of a translation technique employed for a different application.

Claims19

Dependent claims

A computer-implemented method, comprising, during execution of a first application:

receiving, on behalf of said first application, a first memory request directed to a first virtual memory address;
translating said first virtual memory address to a corresponding first physical address according to a first address translation technique;
analyzing performance of said first application;
dynamically selecting a second address translation technique for translating virtual memory addresses to corresponding physical memory addresses on behalf of said first application;
and
subsequent to said selecting a second address translation technique, receiving, on behalf of said first application, a second memory request directed to a second virtual memory address, and translating said second virtual memory address to a corresponding second physical address according to said second address translation technique;
wherein said dynamically selecting a second address translation technique is dependent, at least in part, on a user policy and on results of said analyzing;
and
wherein said dynamically selecting and said translating according to said second address translation technique are performed transparently to said first application.

6 more elements

A computer system, comprising:

a processor configured to support a plurality of memory virtualization techniques;
and
a memory configured to communicate with said processor;
wherein said processor is further configured to:
determine a first one of said plurality of address translation techniques dependent on a predicted distribution of virtual memory locations to be accessed by a first application;
translate, on behalf of said first application executing on said processor, a memory request directed to a first virtual memory address to a first physical memory address of said memory according to said first one of said plurality of memory virtualization techniques;
during said executing, dynamically select a second one of said plurality of memory virtualization techniques for translating virtual addresses, on behalf of said first application, to corresponding physical addresses of said memory;
during said executing and subsequent to said selecting a second one of said plurality of memory virtualization techniques, translate, on behalf of said first application, a second memory request directed to a virtual memory address to a corresponding physical memory address of said memory according to said second one of said plurality of memory virtualization techniques;
wherein said dynamically selecting and said translating according to said second one of said plurality of memory virtualization techniques are performed transparently to said first application.

6 more elements

A processor, comprising:

an address translator configured to support a plurality of memory virtualization techniques;
and
a virtualization technique selector;
wherein said address translator is configured to translate, on behalf of a first application executing on said processor, a memory request directed to a first virtual memory address to a first physical memory address according to a first memory virtualization technique;
wherein said virtualization technique selector is configured to dynamically select a second memory virtualization technique for translating virtual addresses to physical addresses on behalf of said first application during said executing;
wherein said first memory virtualization technique comprises translating virtual addresses to physical addresses using one or more look-up operations on a stored mapping of virtual addresses to physical addresses;
wherein said second memory virtualization technique comprises translating virtual addresses to physical addresses by generating physical addresses from respective virtual addresses using a mathematical or logical function applied to the respective virtual addresses without performing a look-up operation on a stored mapping of virtual addresses to physical addresses;
wherein, during said executing and subsequent to said virtualization technique selector selecting a second memory virtualization technique, said address translator is configured to translate a second memory request directed to a second virtual memory address to a second physical memory address on behalf of said first application according to said second memory virtualization technique;
and
wherein said dynamically selecting and said translating according to said second memory virtualization technique are performed transparently to said first application.

7 more elements

Dependencies are inferred from the claim text.

Dynamic selection of memory virtualization techniques

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Dynamic selection of memory virtualization techniques

Life of this patent

Abstract

Claims19