@Override public KeyGroupsStateHandle performOperation() throws Exception { long asyncStartTime = System.currentTimeMillis(); CheckpointStreamFactory.CheckpointStateOutputStream stream = getIoHandle(); DataOutputViewStreamWrapper outView = new DataOutputViewStreamWrapper(stream); serializationProxy.write(outView); long[] keyGroupRangeOffsets = new long[keyGroupRange.getNumberOfKeyGroups()]; for (int keyGroupPos = 0; keyGroupPos < keyGroupRange.getNumberOfKeyGroups(); ++keyGroupPos) { int keyGroupId = keyGroupRange.getKeyGroupId(keyGroupPos); keyGroupRangeOffsets[keyGroupPos] = stream.getPos(); outView.writeInt(keyGroupId); for (Map.Entry<String, StateTable<K, ?, ?>> kvState : stateTables.entrySet()) { outView.writeShort(kVStateToId.get(kvState.getKey())); cowStateStableSnapshots.get(kvState.getValue()).writeMappingsInKeyGroup(outView, keyGroupId); } } final StreamStateHandle streamStateHandle = closeStreamAndGetStateHandle(); if (asynchronousSnapshots) { LOG.info("Heap backend snapshot ({}, asynchronous part) in thread {} took {} ms.", streamFactory, Thread.currentThread(), (System.currentTimeMillis() - asyncStartTime)); } if (streamStateHandle == null) { return null; } KeyGroupRangeOffsets offsets = new KeyGroupRangeOffsets(keyGroupRange, keyGroupRangeOffsets); final KeyGroupsStateHandle keyGroupsStateHandle = new KeyGroupsStateHandle(offsets, streamStateHandle); return keyGroupsStateHandle; } };