java.lang.OutOfMemoryError: GC overhead limit exceeded

[Antony Mayi]

Hi,
I am using spark.yarn.executor.memoryOverhead=8192 yet getting executors 
crashed with this error.
does that mean I have genuinely not enough RAM or is this matter of config 
tuning?
other config options used:spark.storage.memoryFraction=0.3
SPARK_EXECUTOR_MEMORY=14G
running spark 1.2.0 as yarn-client on cluster of 10 nodes (the workload is ALS 
trainImplicit on ~15GB dataset)
thanks for any ideas,Antony.