Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches

Direct-mapped caches are a popular design choice for high-performance processors; unfortunately, direct-mapped caches suffer systematic interference misses when more than one address map into the same cache set. This paper describes the design of column-associative caches, which minimize the conflic...

Full description

Bibliographic Details
Main Authors: Agarwal, Anant, Pudar, Steven D.
Published: 2023
Online Access:https://hdl.handle.net/1721.1/149210
_version_ 1811078408795324416
author Agarwal, Anant
Pudar, Steven D.
author_facet Agarwal, Anant
Pudar, Steven D.
author_sort Agarwal, Anant
collection MIT
description Direct-mapped caches are a popular design choice for high-performance processors; unfortunately, direct-mapped caches suffer systematic interference misses when more than one address map into the same cache set. This paper describes the design of column-associative caches, which minimize the conflicts that arise in direct-mapped accesses by allowing conflicting addresses to dynamically choose alternate hashing functions, so that most of the conflicting data can reside in the cache. At the same time, however, the critical hit access path is unchanged. The key to implementing this scheme efficiently is the addition to each cache set of a rehash bit, which indicates whether that set stores data that is referenced by an alternate hashing function. When multiple addresses map into the same location, these rehashed locations are preferentially replaced. We demonstrate using trace-driven simulations and an analytical model that a column-associative cache removed virtually all interference misses for large caches, without altering the critical hit access time.
first_indexed 2024-09-23T10:59:02Z
id mit-1721.1/149210
institution Massachusetts Institute of Technology
last_indexed 2024-09-23T10:59:02Z
publishDate 2023
record_format dspace
spelling mit-1721.1/1492102023-03-30T03:57:24Z Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches Agarwal, Anant Pudar, Steven D. Direct-mapped caches are a popular design choice for high-performance processors; unfortunately, direct-mapped caches suffer systematic interference misses when more than one address map into the same cache set. This paper describes the design of column-associative caches, which minimize the conflicts that arise in direct-mapped accesses by allowing conflicting addresses to dynamically choose alternate hashing functions, so that most of the conflicting data can reside in the cache. At the same time, however, the critical hit access path is unchanged. The key to implementing this scheme efficiently is the addition to each cache set of a rehash bit, which indicates whether that set stores data that is referenced by an alternate hashing function. When multiple addresses map into the same location, these rehashed locations are preferentially replaced. We demonstrate using trace-driven simulations and an analytical model that a column-associative cache removed virtually all interference misses for large caches, without altering the critical hit access time. 2023-03-29T14:36:56Z 2023-03-29T14:36:56Z 1993-11 https://hdl.handle.net/1721.1/149210 MIT-LCS-TM-489 application/pdf
spellingShingle Agarwal, Anant
Pudar, Steven D.
Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches
title Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches
title_full Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches
title_fullStr Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches
title_full_unstemmed Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches
title_short Column-associative Caches: A Technique for Reducing the Miss Rate of Direct-mapped Caches
title_sort column associative caches a technique for reducing the miss rate of direct mapped caches
url https://hdl.handle.net/1721.1/149210
work_keys_str_mv AT agarwalanant columnassociativecachesatechniqueforreducingthemissrateofdirectmappedcaches
AT pudarstevend columnassociativecachesatechniqueforreducingthemissrateofdirectmappedcaches