我的工作停止了这样的日志消息：
Waiting for resources for GetStateData.
Memory is used/total/max = 20290/31717/40041 MB,
GC last/max = 71.00/80.00 %, #pushbacks=2, gc thrashing=true
timestamp 2018-03-14T08:16:36.562Z
logger com.google.cloud.dataflow.worker.util.MemoryMonitor
看起来可用内存有问题。谁能证实这一点？任何想法如何调试这类问题？