Hello, I have a pretty weird issue of ZooKeeper. Everyday around 17:30, my ZooKeeper throws a warning message in log says "fsync-ing the write ahead log in SyncThread:0 took 36919ms which will adversely effect operation latency.File size is 16777232 bytes.". And this causes my clients connected to ZooKeeper being timed out. I have to restart my clients every day.
Though I don't think the size of the txn log file is too big to be handled quickly, still I tried to change parameters to supress the size of txn log. Below is my configuration. preAllocSize=16M snapCount=30000 snapSizeLimitInKb=32M Even with this configuration, I still got the warnings. I also tried to monitor the IO stats on data disk which the data dir of ZooKeeper is in. But the stats were as the same as usual. Can anybody help give suggestions on how to solve or investigate on this issue? I am using ZooKeeper 3.7.2. The IO stats were tps=122, reading=20.1k/s, writing=2M/s, when the warning was happening. Best regards, Bill
