Wiki / Configuration Parameters
wal_init_zero
If set to on (the default), this option causes new WAL files to be filled with zeroes. On some file systems, this ensures that space is allocated before we need to write WAL records. However, Copy-On-Write (COW) file systems may not benefit from this technique, so the option is given to skip the unnecessary work. If set to off, only the final byte is written when the file is created so that it has the expected size.
English manual coverage begins with PostgreSQL 7.4. Source history and runtime observations have their own recorded version boundaries.
Reading PG 18·Select a recorded version
- boot val
- on
- category
- Write-Ahead Log / Settings
- context
- superuser
- documented
- true
- enumvals
- Unknown
- extra desc
- Unknown
- lang
- en
- max val
- Unknown
- metadata version
- 18
- min val
- Unknown
- name
- wal_init_zero
- short desc
- Writes zeroes to new WAL files before first use.
- source
- pg-settings-source-snapshot
- unit
- Unknown
- vartype
- bool
Definition PG 18
If set to on (the default), this option causes new WAL files to be filled with zeroes. On some file systems, this ensures that space is allocated before we need to write WAL records. However, Copy-On-Write (COW) file systems may not benefit from this technique, so the option is given to skip the unnecessary work. If set to off, only the final byte is written when the file is created so that it has the expected size.
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center · PostgreSQL 18 · wiki-repair-20261023:b5e24bd30817aa137b4df03cecc86ef760d64e08919f5fa3ae65d7a7571a40ed
Text language: en · wiki-repair-20261023:b5e24bd30817aa137b4df03cecc86ef760d64e08919f5fa3ae65d7a7571a40ed