[SPARK-5252] Streaming StatefulNetworkWordCount example hangs

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.0
• Fix Version/s: 1.3.0
• Component/s: DStreams, Examples, PySpark

Environment

Ubuntu Linux

• Assignee: Davies Liu
• Reporter: Lutz Buech
• Created: 14/Jan/15 17:09
• Updated: 23/Apr/15 19:37
• Resolved: 23/Apr/15 19:37

Description

Running the stateful network word count example in Python (on one local node):
https://github.com/apache/spark/blob/master/examples/src/main/python/streaming/stateful_network_wordcount.py

At the beginning, when no data is streamed, empty status outputs are generated, only decorated by the current Time, e.g.:
-------------------------------------------
Time: 2015-01-14 17:58:20
-------------------------------------------

-------------------------------------------
Time: 2015-01-14 17:58:21
-------------------------------------------

As soon as I stream some data via netcat, no new status updates will show. Instead, one line saying

[Stage <number>:====================================================> (2 + 0) / 3]

where <number> is some integer number, e.g. 132. There is no further output on stdout.