Apache Spark executor uses more than one core despite of spark.executor.cores=1

When I start Apache Spark application on CentOS 6.5, I receive more than 100% load for executors in accordance to 'top' output and load average is significant more than amount of cores.

As a result I have high load on garbage collector.

• Have tried to limit cores per executor with spark.executor.cores=1.


• Have tried spark.cores. No any effect.


• Hardware is Intel(R) Xeon(R) CPU E5-2620 v2 @ 2.10GHz, 6 physical cores.


• Deployment model is YARN client.

Similar Ubuntu 14.04 setup with 4 physical cores (Intel i5) has no any issue, 1 core per executor.

Any idea how to fix this?