Name
Abstract | ||
|---|---|---|
Low-latency remote-write networks, such as DEC’s Memory Channel, provide the possibility of transparent, inexpensive, huge-scale shared-memory parallel computing on clusters of shared memory multiprocessors (SMPs). The challenge is to take advantage of hardwaresharedmemoryfor sharing within an SMI: and to ensure that software overheadis incurredonly when actively sharing data across SMPs in the cluster. In this paper, we describe a ‘Ywolevel” software coherent shared memory system-Cashmere-2Lthat meets this challenge. CashmereSL uses hardware to share memory within a node, while exploiting the Memory Channel’s remote-write capabilities to implement “moderately lazy” release consistency with multiple concurrent writers, directories, home nodes, and page-size coherence blocks across nodes. Cashmere2L employs a novel coherence protocol that allows a high level of asynchrony by eliminating global directory locks and the needfor TLB shootdown. Remote interrupts are minimized by exploiting the remote-write capabilities of the Memory Channel network Cashmere-2L currently runs on an &node, 32-processor DEC AlphaServersystem. Speedups rangefrom 8 to 31 on 32processors for our benchmark suite, depending on the application’s characteristics. We quanhfi the importance of ourprotocol optimizations by comparing perjormance to that of several alternative protocols that do not share memory in hardware within an SMP, and require more synchronization. In comparison to a one-level protocol that does not share memory in hardware within an SMP Cashmere-2L improves performance by up to 46%. |
Year | DOI | Venue |
|---|---|---|
1997 | 10.1145/268998.266675 | SOSP |
Keywords | Field | DocType |
software coherent shared memory,remote-write network,parallel computer,low latency,shared memory | Registered memory,Interleaved memory,Uniform memory access,Shared memory,Computer science,Distributed memory,Memory management,Memory map,Distributed shared memory,Operating system | Conference |
Volume | Issue | ISSN |
31 | 5 | 0163-5980 |
ISBN | Citations | PageRank |
0-89791-916-5 | 95 | 7.59 |
References | Authors | |
16 | 7 | |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Robert Stets | 1 | 444 | 67.87 |
| Sandhya Dwarkadas | 2 | 3504 | 257.31 |
| Nikolaos Hardavellas | 3 | 226 | 20.82 |
| Galen C. Hunt | 4 | 889 | 61.08 |
| Leonidas Kontothanassis | 5 | 115 | 9.70 |
| Srinivasan Parthasarathy | 6 | 4666 | 375.76 |
| Michael L. Scott | 7 | 2843 | 248.01 |