Prometheus TSDB (Part 2): WAL and Checkpoint
Ganesh Vernekar
Software Engineer @ Grafana LabsIntroduction
In the Part 1 of the TSDB blog series I mentioned that we write the incoming samples into Write-Ahead-Log (WAL) first for durability and that when this WAL is truncated, a checkpoint is created. In this blog post, we will briefly discuss the basics of WAL and then dive into how WAL and checkpoints are designed in Prometheus' TSDB.