Hi, I'm facing a problem where Spark is able to perform an action on a cached RDD correctly the first time it is run, but running it immediately afterwards (or an action depending on that RDD) causes it to get stuck.
I'm using a MongoDB connector for fetching all documents from a collection to an RDD and caching that (though according to the error message it doesn't fully fit). The first action on it always succeeds, but latter actions fail. I just upgraded from Spark 0.9.x to 1.5.1, and didn't have that problem with the older version. The output I get: scala> analyticsRDD.cache res10: analyticsRDD.type = MapPartitionsRDD[84] at map at Mongo.scala:69 scala> analyticsRDD.count [Stage 2:=================================================> (472 + 8) / 524]15/10/30 14:20:00 WARN MemoryStore: Not enough space to cache rdd_84_469 in memory! (computed 13.0 MB so far) 15/10/30 14:20:00 WARN MemoryStore: Not enough space to cache rdd_84_470 in memory! (computed 12.1 MB so far) 15/10/30 14:20:00 WARN MemoryStore: Not enough space to cache rdd_84_476 in memory! (computed 5.6 MB so far) ... 15/10/30 14:20:06 WARN MemoryStore: Not enough space to cache rdd_84_522 in memory! (computed 5.3 MB so far) [Stage 2:======================================================>(522 + 2) / 524]15/10/30 14:20:06 WARN MemoryStore: Not enough space to cache rdd_84_521 in memory! (computed 13.9 MB so far) res11: Long = 7754957 scala> analyticsRDD.count [Stage 3:=================================================> (474 + 0) / 524] *** Restart Spark *** scala> analyticsRDD.count res10: Long = 7755043 scala> analyticsRDD.count res11: Long = 7755050 The cached RDD always gets stuck at the same point. I tried enabling full debug logging, but couldn't make out anything useful. I'm also facing another issue with loading a lot of data from MongoDB, which might be related, but the error is different: https://groups.google.com/forum/#!topic/mongodb-user/Knj406szd74 Any ideas? * Sampo Niskanen* *Lead developer / Wellmo* sampo.niska...@wellmo.com +358 40 820 5291
