Method and apparatus to purge remote node cache lines to support hot node replace in a computing system

摘要

An apparatus and method is disclosed for flushing a cache in a computing system. In a multinode computing system a cache in a first node may contain modified data in an address space of a second node. The cache in the first node must be purged prior to shutting down the first node. The computing system uses a random class replacement scheme for the cache. A cache flush routine sets a cache flush mode in a class replace select mechanism, overriding the random class replacement scheme. With the random class replacement scheme overridden, a minimum number of fetches will flush all the cache lines in the cache, each fetch loading the cache with a cache line not already in the cache. No additional delay penalty is incurred in a critical path through which fetches and stores to the cache must pass.