Yin, Jieming | Search NASA

DOE OSTI2023

Cache management based on reuse distance

A cache of a processor includes a cache controller to implement a cache management policy for the insertion and replacement of cache lines of the cache. The cache management policy assigns replacement priority levels to each cache line of at least a subset of cache lines in a region of the cache based on a comparison of a number of accesses to a cache set having a way that stores a cache line since the cache line was last accessed to a reuse distance determined for the region of the cache, wherein the reuse distance represents an average number of accesses to a given cache set of the region between accesses to any given cache line of the cache set.

Yin, Jieming↗

DOE OSTI2023

Cache management based on access type priority

Systems, apparatuses, and methods for cache management based on access type priority are disclosed. A system includes at least a processor and a cache. During a program execution phase, certain access types are more likely to cause demand hits in the cache than others. Demand hits are load and store hits to the cache. A run-time profiling mechanism is employed to find which access types are more likely to cause demand hits. Based on the profiling results, the cache lines that will likely be accessed in the future are retained based on their most recent access type. The goal is to increase demand hits and thereby improve system performance. An efficient cache replacement policy can potentially reduce redundant data movement, thereby improving system performance and reducing energy consumption.

Yin, Jieming↗

DOE OSTI2020

Using predictions of outcomes of cache memory access requests for controlling whether a request generator sends memory access requests to a memory in parallel with cache memory access requests

An electronic device handles memory access requests for data in a memory. The electronic device includes a memory controller for the memory, a last-level cache memory, a request generator, and a predictor. The predictor determines a likelihood that a cache memory access request for data at a given address will hit in the last-level cache memory. Based on the likelihood, the predictor determines: whether a memory access request is to be sent by the request generator to the memory controller for the data in parallel with the cache memory access request being resolved in the last-level cache memory, and, when the memory access request is to be sent, a type of memory access request that is to be sent. When the memory access request is to be sent, the predictor causes the request generator to send a memory request of the type to the memory controller.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2019

Setting operating points for circuits in an integrated circuit chip

The described embodiments include an apparatus that controls voltages for an integrated circuit chip having a set of circuits. The apparatus includes a switching voltage regulator separate from the integrated circuit chip and two or more low dropout (LDO) regulators fabricated on the integrated circuit chip. The switching voltage regulator provides an output voltage that is received as an input voltage by each of the two or more LDO regulators, and each of the two or more LDO regulators provides a local output voltage, each local output voltage received as a local input voltage by a different subset of the circuits in the set of circuits. During operation, a controller sets an operating point for each of the subsets of circuits based on a combined power efficiency for the subsets of the circuits and the LDO regulators, each operating point including a corresponding frequency and voltage.

Huang, Wei↗

DOE OSTI2018

Setting operating points for circuits in an integrated circuit chip

The described embodiments include an apparatus that controls voltages for an integrated circuit chip having a set of circuits. The apparatus includes a switching voltage regulator separate from the integrated circuit chip and two or more low dropout (LDO) regulators fabricated on the integrated circuit chip. The switching voltage regulator provides an output voltage that is received as an input voltage by each of the two or more LDO regulators, and each of the two or more LDO regulators provides a local output voltage, each local output voltage received as a local input voltage by a different subset of the circuits in the set of circuits. During operation, a controller sets an operating point for each of the subsets of circuits based on a combined power efficiency for the subsets of the circuits and the LDO regulators, each operating point including a corresponding frequency and voltage.

42 ENGINEERING↗