Grand Central Dispatch (
GCD) is a technology developed by
Apple Inc. to optimize application support for systems with
multi-core processors and other
symmetric multiprocessing systems. It is an implementation of
task parallelism based on the
thread pool pattern. The fundamental idea is to move the management of the thread pool out of the hands of the developer, and closer to the operating system. The developer injects "work packages" into the pool oblivious of the pool's architecture. This model improves simplicity, portability and performance.