Search results
Results from the WOW.Com Content Network
Diagram of a symmetric multiprocessing system. Symmetric multiprocessing or shared-memory multiprocessing [1] (SMP) involves a multiprocessor computer hardware and software architecture where two or more identical processors are connected to a single, shared main memory, have full access to all input and output devices, and are controlled by a single operating system instance that treats all ...
HSA defines a special case of memory sharing, where the MMU of the CPU and the IOMMU of the GPU have an identical pageable virtual address space.. In computer hardware, shared memory refers to a (typically large) block of random access memory (RAM) that can be accessed by several different central processing units (CPUs) in a multiprocessor computer system.
With the (IBM) SPMD model the cooperating processors (or processes) take different paths through the program, using parallel directives (parallelization and synchronization directives, which can utilize compare-and-swap and fetch-and-add operations on shared memory synchronization variables), and perform operations on data in the shared memory ...
The traffic can be reduced by using a cache that acts as a "filter" versus the shared memory, that is the cache is an essential element for shared-memory in SMP systems. In multiprocessor systems with separate caches that share a common memory, a same datum can be stored in more than one cache.
Tightly coupled multiprocessor systems contain multiple CPUs that are connected at the bus level. These CPUs may have access to a central shared memory (SMP or UMA), or may participate in a memory hierarchy with both local and shared memory (SM). The IBM p690 Regatta is an example of a high end SMP system.
Multiprocessor system with a shared memory closely connected to the processors. A symmetric multiprocessing system is a system with centralized shared memory called main memory (MM) operating under a single operating system with two or more homogeneous processors. There are two types of systems: Uniform memory-access (UMA) system; NUMA system
Another advantage is that memory coherence is managed by the operating system and not the written program. Two known disadvantages are: scalability beyond thirty-two processors is difficult, and the shared memory model is less flexible than the distributed memory model. [4] There are many examples of shared memory (multiprocessors): UMA ...
Uniform memory access (UMA) is a shared memory architecture used in parallel computers.All the processors in the UMA model share the physical memory uniformly. In an UMA architecture, access time to a memory location is independent of which processor makes the request or which memory chip contains the transferred data.