Silent cache line eviction
AssigneeMicron Technology, Inc.
InventorsTony M. Brewer, Dean E. Walker
Life of this patent
Estimating the term…
Abstract
System and techniques for silent cache line eviction are described herein. A memory device receives a memory operation from a host. The memory operation establishes data and metadata in a cache line of the memory device upon receipt. The metadata is stored in a memory element that corresponds to the cache line. Later, an eviction trigger to evict the cache line is identified. Then, in response to the eviction trigger, current metadata of the cache line is compared with the metadata in the memory element to determine whether the metadata has changed. the cache line can be evicted without writing to backing memory in response to the metadata being unchanged.
Claims20
A cache device comprising:
- a first interface configured to receive a memory operation;
- a second interface configured to communicate with a memory device;
- a storage device with a portion configured as a cache line;
- and
- processing circuitry configured to:
- track metadata changes for the cache line between writebacks to the memory device by:
- recording first cache line metadata when metadata is originally written to the cache line separately from current cache line metadata;
- and
- comparing the current cache line metadata to the first cache line metadata based on an eviction event to produce an indicator whether there is a difference between the first cache line metadata and the current cache line metadata;
- and
- writeback the metadata to the memory device as part of an eviction of the cache line only when the indicator of whether there is a difference between the first cache line metadata and the current cache line metadata indicates that there is a difference or a dirty flag is present on the cache line.
A method comprising:
- receiving, at a first interface of a cache device, a memory operation;
- tracking, by a cache device, changes to metadata for a cache line of a memory device connected to the cache device by a second interface, including:
- recording first cache line metadata when metadata is originally written to the cache line separately from current cache line metadata;
- and
- comparing the current cache line metadata to the first cache line metadata based on an eviction event to produce an indicator whether there is a difference between the first cache line metadata and the current cache line metadata;
- and
- writing back the metadata to the memory device as part of an eviction of the cache line only when the indicator of whether there is a difference between the first cache line metadata and the current cache line metadata indicates that there is a difference or a dirty flag is present on the cache line.
Dependencies are inferred from the claim text.