kafka Shrinking ISR后，集群某个节点打开文件数剧增

kafka集群打开文件数突然剧增，原来一直很稳定在2K左右，突然飙升到3W多，然后导致kafka集群无法写入。偶尔就会出现一次，需要重启节点才能恢复。

目前观察到的日志如下

Shrinking ISR for partition [__consumer_offsets,49] from 232,236,234 to 234
Shrinking ISR for partition [__consumer_offsets,44] from 234,236 to 234
Shrinking ISR for partition [FlowStatisticsTopic,3] from 234,233 to 234 
Shrinking ISR for partition [LinkTrackingTopic,4] from 232,236,234,233 to 234

这种的比较集中，然后接着，就出现

Connection to 233 was disconnected before the response was read
Connection to 234 was disconnected before the response was read
Connection to 232 was disconnected before the response was read

这样的错误，但是其它都自定连接上了234这就会报出Too many open files。

请问下，这种问题是由什么导致的。