I heard that ZooKeeper uses Write Ahead Log for preserving operation information, and am interested in how it's implemented. But when checking ZooKeeper confluence wiki and searching the internet, I don't find much related documents. Only a few source files such as FileTxnLog.java that seems to be related with some lines written directly about write ahead log string.

https://github.com/apache/zookeeper/blob/5c4e44332e55bbf21ca59583f3e8ca97fc4bb266/src/java/main/org/apache/zookeeper/server/persistence/FileTxnLog.java

Is this the right place to start? What other resources available out there as reference?

Thanks
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