JBoss Data Grid (Infinispan) uses JBoss Marshalling internally. When a replication object contains huge serialization data (e.g. an object contains a huge size of List<String> as a field, etc). IdentityIntMap has the possibility to have a huge size array. And since it will not shrink afterward, it will continue to hold more size than necessary, and the subsequent clear() call can take longer than expected because of invoking "Arrays.fill(keys, null)" against a huge array. Subsequent replication of large amounts of data may lead to transaction timeouts due to the increased cost of the clear().