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<chapter id="wal">

<title>Reliability and the Write-Ahead Log</title>

directory. A restartpoint is triggered if at least one checkpoint record

has been replayed and <varname>checkpoint_timeout</> seconds have passed

since last restartpoint. In standby mode, a restartpoint is also triggered

if <varname>checkoint_segments</> log segments have been replayed since

if <varname>checkpoint_segments</> log segments have been replayed since

last restartpoint and at least one checkpoint record has been replayed.

Restartpoints can't be performed more frequently than checkpoints in the

master because restartpoints can only be performed at checkpoint records.