A method for a cache miss estimation includes; generating a variable range of a possible value of loop variables relevant to a specific array; generating first expression of number of times indicating the number of times the specific position of a specific loop is executed; generating second expression of number of times indicating the number of times the data of the access target is stored in the cache; generating third expression of number of times indicating the number of times the data of the access target is removed from the cache; generating fourth expression of number of times, from a generated conflict miss cause common expression, indicating the number of times the data of the access target is stored in the cache; and estimating a number of cache miss based on the difference between the first and the second expressions and the difference between the third and the forth expressions.

A method for a cache miss estimation includes; generating a variable range of a possible value of loop variables relevant to a specific array; generating first expression of number of times indicating the number of times the specific position of a specific loop is executed; generating second expression of number of times indicating the number of times the data of the access target is stored in the cache; generating third expression of number of times indicating the number of times the data of the access target is removed from the cache; generating fourth expression of number of times, from a generated conflict miss cause common expression, indicating the number of times the data of the access target is stored in the cache; and estimating a number of cache miss based on the difference between the first and the second expressions and the difference between the third and the forth expressions.

A processing system includes a cache that includes a cache lines that are partitioned into a first subset of the cache lines and a second subsets of the cache lines. The processing system also includes one or more counters that are associated with the second subsets of the cache lines. The processing system further includes a processor configured to modify the one or more counters in response to a cache hit or a cache miss associated with the second subsets. The one or more counters are modified by an amount determined by one or more characteristics of a memory access request that generated the cache hit or the cache miss.

A method of managing a direct-mapped cache is provided. The method includes a direct-mapped cache receiving memory references indexed to a particular cache line, using a first cache line replacement algorithm to select a main memory block as a candidate for storage in the cache line in response to each memory reference, and using a second cache line replacement algorithm to select a main memory block as a candidate for storage in the cache line in response to each memory reference. The method further includes identifying, over a plurality of most recently received memory references, which one of the algorithms has selected a main memory block that matches a next memory reference a greater number of times, and storing a block of main memory in the cache line, wherein the block of main memory stored in the cache line is the main memory block selected by the identified algorithm.

A method of managing a direct-mapped cache is provided. The method includes a direct-mapped cache receiving memory references indexed to a particular cache line, using a first cache line replacement algorithm to select a main memory block as a candidate for storage in the cache line in response to each memory reference, and using a second cache line replacement algorithm to select a main memory block as a candidate for storage in the cache line in response to each memory reference. The method further includes identifying, over a plurality of most recently received memory references, which one of the algorithms has selected a main memory block that matches a next memory reference a greater number of times, and storing a block of main memory in the cache line, wherein the block of main memory stored in the cache line is the main memory block selected by the identified algorithm.

A processing system selects entries for eviction at one cache based at least in part on the validity status of corresponding entries at a different cache. The processing system includes a memory hierarchy having at least two caches, a higher level cache and a lower level cache. The lower level cache monitors which locations of the higher level cache have been indicated as invalid and, when selecting an entry of the lower level cache for eviction to the higher level cache, selects the entry based at least in part on whether the selected cache entry will be stored at an invalid cache line of the higher level cache.

A processor replaces data at a first cache based on hints from a second cache, wherein the hints indicate information about the data that is not available to the first cache directly. When data at an entry is transferred from the first cache to the second cache, the first cache can provide an age hint to the second cache to indicate that the data should be assigned a higher or lower initial age relative to a nominal initial age. The second cache assigns the entry for the data an initial age based on the age hint and, when replacing data, selects data for replacement based on the age of each entry.

Guided cache replacement is described. In accordance with the described techniques, a request to access a cache is received, and a cache replacement policy which controls loading data into the cache is accessed. The cache replacement policy includes a tree structure having nodes corresponding to cachelines of the cache and a traversal algorithm controlling traversal of the tree structure to select one of the cachelines. Traversal of the tree structure is guided using the traversal algorithm to select a cacheline to allocate to the request. The guided traversal modifies at least one decision of the traversal algorithm to avoid selection of a non-replaceable cacheline.

In response to eviction of a first clean data block from an intermediate level of cache in a multi-cache hierarchy of a processing system, a cache controller accesses an address of the first clean data block. The controller initiates a fetch of the first clean data block from a system memory into a last-level cache using the accessed address.

This document describes apparatuses and techniques for cache memory with randomized eviction. In various aspects, a cache memory randomly selects a cache line for eviction and/or replacement. The cache memory may also support multi-occupancy whereby the cache memory enters data reused from another cache line to replace the data of the randomly evicted cache line. By so doing, the cache memory may operate in a nondeterministic fashion, which may increase a probability of data remaining in the cache memory for subsequent requests.