[infinispan-issues] [JBoss JIRA] (ISPN-1115) Fine-grained AtomicMaps

Fine-grained AtomicMaps ----------------------- Key: ISPN-1115 URL: https://issues.jboss.org/browse/ISPN-1115 Project: Infinispan Issue Type: Feature Request Components: Core API Reporter: Manik Surtani Assignee: Vladimir Blagojevic Priority: Blocker Fix For: 5.1.0.BETA2, 5.1.0.FINAL Atomic Maps are locked by acquiring a single lock on the entire map and this causes concurrency issues for certain use cases. This JIRA is to allow for concurrent modifications of keys within the AtomicMap, provided the keys do not overlap. The design is as follows: * {{AtomicMapLookup}} gets a WL on the {{AtomicMap}}'s key (AMK) when creating and removing a new AtomicMap * Modifications to the AtomicMap (which go through the {{AtomicMapProxy}}) do _not_ acquire a WL on AMK. Instead, * {{AdvancedCache}} exposes a new API, {{applyDelta(K deltaAwareValueKey, Delta delta, Object... locksToAcquire)}} * {{AtomicMapProxy}} makes changes by calling {{applyDelta}} and passing in the key within the map that is being modified, along with the delta to apply. * The implementation could offer lock pooling to prevent a large number of locks being created for AtomicMaps with a large number of entries * On detecting concurrent deletion, updates would fail. This can then be used by other {{Delta}}/{{DeltaAware}} types in future as well, perhaps JSON documents, etc.