Github user arunmahadevan commented on a diff in the pull request: https://github.com/apache/storm/pull/1470#discussion_r68537734 --- Diff: external/storm-redis/src/main/java/org/apache/storm/redis/state/RedisKeyValueState.java --- @@ -161,7 +176,11 @@ public void prepareCommit(long txid) { commands = jedisContainer.getInstance(); if (commands.exists(prepareNamespace)) { LOG.debug("Prepared txn already exists, will merge", txid); - pendingPrepare.putAll(pendingCommit); + for (Map.Entry<String, String> e: pendingCommit.entrySet()) { + if (!pendingPrepare.containsKey(e.getKey())) { + pendingPrepare.put(e.getKey(), e.getValue()); + } + } } if (!pendingPrepare.isEmpty()) { commands.hmset(prepareNamespace, pendingPrepare); --- End diff -- A potential issue (already existing) which could be fixed here or in a separate JIRA. If the pendingPrepare is updated after the hmset but before its assigned to pendingCommit, the pendingCommit will not reflect the entities in prepareNamespace. I think if the pendingPrepare is snapshotted/copied before hmset and the copy is used for both hmset and assigned to pendingCommit it would avoid this race condition.
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. ---