Hi, This happens when I hammer our 5 kafka streaming nodes (each with 4 streaming threads) hard enough for an hour or so:
2016-10-23 13:04:17 ERROR StreamThread:324 - stream-thread [StreamThread-2] Failed to flush state for StreamTask 3_8: org.apache.kafka.streams.errors.ProcessorStateException: task [3_8] Failed to flush state store streams-data-record-stats-avro-br-store at org.apache.kafka.streams.processor.internals.ProcessorStateManager.flush(ProcessorStateManager.java:322) at org.apache.kafka.streams.processor.internals.AbstractTask.flushState(AbstractTask.java:181) at org.apache.kafka.streams.processor.internals.StreamThread$4.apply(StreamThread.java:360) at org.apache.kafka.streams.processor.internals.StreamThread.performOnAllTasks(StreamThread.java:322) at org.apache.kafka.streams.processor.internals.StreamThread.flushAllState(StreamThread.java:357) at org.apache.kafka.streams.processor.internals.StreamThread.shutdownTasksAndState(StreamThread.java:295) at org.apache.kafka.streams.processor.internals.StreamThread.shutdown(StreamThread.java:262) at org.apache.kafka.streams.processor.internals.StreamThread.run(StreamThread.java:245) Caused by: org.apache.kafka.streams.errors.ProcessorStateException: Error opening store streams-data-record-stats-avro-br-store-201505160000 at location /tmp/kafka-streams/argyle-streams/3_8/streams-data-record-stats-avro-br-store/streams-data-record-stats-avro-br-store-201505160000 at org.apache.kafka.streams.state.internals.RocksDBStore.openDB(RocksDBStore.java:196) at org.apache.kafka.streams.state.internals.RocksDBStore.openDB(RocksDBStore.java:158) at org.apache.kafka.streams.state.internals.RocksDBWindowStore$Segment.openDB(RocksDBWindowStore.java:72) at org.apache.kafka.streams.state.internals.RocksDBWindowStore.getOrCreateSegment(RocksDBWindowStore.java:402) at org.apache.kafka.streams.state.internals.RocksDBWindowStore.putAndReturnInternalKey(RocksDBWindowStore.java:310) at org.apache.kafka.streams.state.internals.RocksDBWindowStore.put(RocksDBWindowStore.java:292) at org.apache.kafka.streams.state.internals.MeteredWindowStore.put(MeteredWindowStore.java:101) at org.apache.kafka.streams.state.internals.CachingWindowStore$1.apply(CachingWindowStore.java:87) at org.apache.kafka.streams.state.internals.NamedCache.flush(NamedCache.java:117) at org.apache.kafka.streams.state.internals.ThreadCache.flush(ThreadCache.java:100) at org.apache.kafka.streams.state.internals.CachingWindowStore.flush(CachingWindowStore.java:118) at org.apache.kafka.streams.processor.internals.ProcessorStateManager.flush(ProcessorStateManager.java:320) ... 7 more Caused by: org.rocksdb.RocksDBException: IO error: lock /tmp/kafka-streams/argyle-streams/3_8/streams-data-record-stats-avro-br-store/streams-data-record-stats-avro-br-store-201505160000/LOCK: No locks available at org.rocksdb.RocksDB.open(Native Method) at org.rocksdb.RocksDB.open(RocksDB.java:184) at org.apache.kafka.streams.state.internals.RocksDBStore.openDB(RocksDBStore.java:189) ... 18 more Some sort of a locking bug? Note that when this happen this node stops processing anything and the other nodes seem to want to pick up the load, which brings the whole streaming cluster to a stand still. That’s very worrying. Is a document somewhere describing *in detail* how failover for streaming works? Ara. ________________________________ This message is for the designated recipient only and may contain privileged, proprietary, or otherwise confidential information. If you have received it in error, please notify the sender immediately and delete the original. Any other use of the e-mail by you is prohibited. Thank you in advance for your cooperation. ________________________________
