Distributed shared memory

In computer science, distributed shared memory (DSM) is a form of memory architecture where physically separated memories can be addressed as a single shared address space. The term "shared" does not mean that there is a single centralized memory, but that the address space is shared—i.e., the same physical address on two processors refers to the same location in memory.^[1]^: 201 Distributed global address space (DGAS), is a similar term for a wide class of software and hardware implementations, in which each node of a cluster has access to shared memory in addition to each node's private (i.e., not shared) memory.

"DGAS" redirects here. For the DGA awards, see Directors Guild of America Award.

-based approach using virtual memory

Page

Shared-variable approach using routines to access shared variables

Object-based approach, ideally accessing shared data through object-oriented discipline

Reduce network traffic

Promote increased parallelism

Result in fewer page faults

There are two types of replication Algorithms. Read replication and Write replication. In Read replication multiple nodes can read at the same time but only one node can write. In Write replication multiple nodes can read and write at the same time. The write requests are handled by a sequencer. Replication of shared data in general tends to:

However, preserving coherence and consistency may become more challenging.

Release consistency: when a process exits a , new values of the variables are propagated to all sites.

critical section

VODCA

– Type of computer cache

Distributed cache

– Computer science term

Memory virtualization

– Cluster dedicated operating system

Single-system image

– Low-level hardware direct memory access

Remote direct memory access

Distributed Shared Cache

by Kai Li, Paul Hudak published in ACM Transactions on Computer Systems, Volume 7 Issue 4, Nov. 1989