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WAL & Replication

The WAL tab shows the current state of Write-Ahead Logging and replication on the connected instance.

What it shows​

  • Current WAL LSN — the current write position in the WAL stream.
  • WAL generation rate — bytes per second derived from LSN deltas in performance samples.
  • Replication status — synchronous or asynchronous, with replica write lag when applicable.
  • Replication slots — both active and inactive slots with their WAL retention lag.

Refresh​

The WAL tab has a manual Refresh button. Unlike some tabs, it does not auto-refresh — the data changes slowly enough that manual refresh is sufficient.

Connection to tuning​

WAL samples collected on this tab feed directly into tuning recommendations:

  • max_wal_size — sized from peak WAL rate, checkpoint timeout, and completion target.
  • min_wal_size — companion recommendation kept proportional to the larger WAL budget.
  • wal_compression — recommended when WAL volume is high enough for compression to be worth considering.
  • Checkpoint diagnosis — determines whether requested checkpoints are caused by WAL pressure, administrative tasks, or a mix.

pocketPG separates application WAL pressure from administrative/provider checkpoint activity so it does not recommend increasing WAL settings for the wrong reason.