Write Skew check must be performed only in the primary owner ------------------------------------------------------------ Key: ISPN-3419 URL: https://issues.jboss.org/browse/ISPN-3419 Project: Infinispan Issue Type: Bug Components: Transactions Affects Versions: 6.0.0.Alpha2 Reporter: Pedro Ruivo Assignee: Pedro Ruivo Fix For: 6.0.0.Beta1 The following case can create data inconsistency: A: txA reads k with version v1 and writes on k (say valueA) primary-owner of k: txA acquire lock on k, validates and return v2 (increment(v1)) non-primary-onwer of k: txA registers a backup lock, validates and returns v2 (increment(v1)) A: txA commits with version v2. primary-owner of k: applies txA //commit in the non-primary-owner is delayed B: txB remote reads k with version v2 and writes on k (say valueB) and prepare the transaction primary-owner of k: txB waits until the lock is relased. non-primary-onwer of k: txA registers a backup lock, validates and returns v2 (increment(v1), because it has not applied the txA) primary-owner of k: lock is release, txB is validated and it return v3 (increment(v2)) B collects all the response and merge them. However, the map.value() can return first the response from primary-owner (v3) and them the response from the non-primary-owner (v2). The result version map will be k=>v2. txB will update k with the same previous version and a different value. from here the data will become inconsistent.