Advanced Micro Devices Corporation

Richard E Klass

John Kalamatianos

Michael L Golden

James Michael O'Connor

Srilatha Manne

Marius Evers

Edward J McLellan

Ravindra Nath Bhargava

Paul S Keltcher

Carl D Dietz

The present application describes embodiments of techniques for picking a data array lookup request for execution in a data array pipeline a variable number of cycles behind a corresponding tag array lookup request that is concurrently executing in a tag array pipeline. Some embodiments of a method for picking the data array lookup request include picking the data array lookup request for execution in a data array pipeline of a cache concurrently with execution of a tag array lookup request in a tag array pipeline of the cache. The data array lookup request is picked for execution in response to resources of the data array pipeline becoming available after picking the tag array lookup request for execution. Some embodiments of the method may be implemented in a cache.

Variable distance bypass between tag array and data array pipelines in a cache

In response to a processor core exiting a low-power state, a cache is set to a minimum size so that fewer than all of the cache's entries are available to store data, thus reducing the cache's power consumption. Over time, the size of the cache can be increased to account for heightened processor activity, thus ensuring that processing efficiency is not significantly impacted by a reduced cache size. In some embodiments, the cache size is increased based on a measured processor performance metric, such as an eviction rate of the cache. In some embodiments, the cache size is increased at regular intervals until a maximum size is reached.

Management of cache size

In one embodiment, a processing node includes a first processor core and a second processor core. The first processor core includes a first cache memory, such as an L2 cache, for example. The second processor core includes a second cache memory, such as an L2 cache memory. The processing node further includes a configuration unit that is coupled to the first processor core and the second processor core. The configuration unit may selectably disable portions of the first and the second cache memories.

Reconfigurable processing node including first and second processor cores

In one embodiment, a processing node includes a plurality of processor cores each including a cache memory coupled to a cache monitor unit and to a configuration unit. Each cache monitor unit may be configured to independently monitor a current utilization of the cache memory to which it is coupled and to determine whether the current utilization is below a predetermined utilization value. The configuration unit may selectably disable one or more portions of the cache memory in response to the cache monitor unit determining that the current utilization is below the predetermined utilization value.

Growing community of inventors

Fort Collins, CO, United States of America

Richard E Klass