Dear @kingpin  Thanks for your reply, I do have a sparkstreaming proccess for storing files to hdfs from kafka every two minutes. You can refer the screenshot below for the data volume. The java heap is increasing every day. I think it will be over 70GB after 1 month, but the blocks is still less than 2 million. Is there anyway to clean cache of javaheap？  The memory of java heap will be normal after rebooting. sparkstreaming of car @kingpin    Thanks for your reply, I do have a sparkstreaming proccess for storing files to hdfs from kafka every two minutes. You can refer the screenshot below for the data volume.   The java heap is increasing every day. I think it will be over 70GB after 1 month, but the blocks is still less than 2 million.   Is there anyway to clean cache of javaheap？    The memory of java heap will be normal after rebooting.   sparkstreaming of consuming kakfa: ... View more