Chapter 12. The WAL

HBase's Write-Ahead Log

Table of Contents

12.1. What is the purpose of the HBase WAL
12.2. WAL splitting
12.2.1. hbase.hlog.split.skip.errors
12.2.2. How EOFExceptions are treated when splitting a crashed RegionServers' WALs

Each RegionServer adds updates to its Write-ahead Log (WAL) first, and then to memory.

12.1. What is the purpose of the HBase WAL

See the Wikipedia Write-Ahead Log article.