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<chapter id="wal">

<title>Write-Ahead Logging (<acronym>WAL</acronym>)</title>

divided into 8 kB pages. The log record headers are described in

<filename>access/xlog.h</filename>; record content is dependent on

the type of event that is being logged. Segment files are given

sequential numbers as names, starting at

ever-increasing numbers as names, starting at

<filename>0000000000000000</filename>. The numbers do not wrap, at

present, but it should take a very long time to exhaust the

available stock of numbers.