ZoneTree offers 4 WAL modes to let you make a flexible tradeoff.

• The sync mode provides maximum durability but slower write speed. In case of a crash/power cut, the sync mode ensures that the inserted data is not lost.

• The sync-compressed mode provides faster write speed but less durability. Compression requires chunks to be filled before appending them into the WAL file. It is possible to enable a periodic job to persist decompressed tail records into a separate location in a specified interval. See IWriteAheadLogProvider options for more details.

• The async-compressed mode provides faster write speed but less durability. Log entries are queued to be written in a separate thread. Async-compressed mode uses compression in WAL files.

• None WAL mode disables WAL completely to get maximum performance. Data still can be saved to disk by tree maintainer automatically or manually.