[infinispan-issues] [JBoss JIRA] Reopened: (ISPN-1300) Reduce number of locks and buckets generated by BucketBasedCacheStore

Reduce number of locks and buckets generated by BucketBasedCacheStore --------------------------------------------------------------------- Key: ISPN-1300 URL: https://issues.jboss.org/browse/ISPN-1300 Project: Infinispan Issue Type: Enhancement Components: Configuration, Loaders and Stores Affects Versions: 5.0.0.CR8 Reporter: Robert Stupp Assignee: Manik Surtani Fix For: 5.0.0.FINAL The current implementation of FileCacheStore creates one bucket and lock for each hash key - which results in up to 4.2 billion files (2^32). It should limit the number of files to a) improve performance of purge b) reduce number of open file handles (system resources) c) reduce number of Java objects/heap (JVM resources) d) improve performance The implementation allows us to do so. Only 4 lines of code are necessary in BucketBasedCacheStore implementation: {code} private int hashKeyMask = 0xfffffc00; // TODO should get a configuration entry @Override protected Integer getLockFromKey(Object key) { return Integer.valueOf(key.hashCode() & hashKeyMask); } {code} This reduces the number of files to 2^22 = 4,194,304 files. Since each application and each cache store has different semantics the hasKeyMask value should be configurable - best would be to configure the number of bits. Side effect: If someone changes the FileCacheStore hasKeyMask, the whole cache store becomes unuseable. So I opened another enhancement ... Note: This implementation should be used in a different class (e.g. extend FileCacheStore) because it makes existing file cache stores unusable.