程序异常如下：Caused by: com.datastax.driver.core.exceptions.WriteTimeoutException: Cassandra timeout during write query at consistency LOCAL_ONE (1 replica were required but only 0 acknowledged the write)
原因很显然是coordinator，就是node没有及时响应写完成
解决方法无外乎，减少数据量，提高超时时间
在cassandra.yaml里
# How long the coordinator should wait for writes to complete write_request_timeout_in_ms: 2000 # How long the coordinator should wait for counter writes to complete counter_write_request_timeout_in_ms: 5000
将这2项都调大，默认是2s和5s
调整后，重启节点生效
ps auwx | grep cassandra sudo kill pid bin/cassandra