Wiki / Configuration Parameters
io_max_combine_limit
Controls the largest I/O size in operations that combine I/O, and silently limits the user-settable parameter io_combine_limit. This parameter can only be set at server start. If this value is specified without units, it is taken as blocks, that is BLCKSZ bytes, typically 8kB. The maximum possible size depends on the operating system and block size, but is typically 1MB on Unix and 128kB on Windows. The default is 128kB.
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
- 16
- category
- Resource Usage / I/O
- context
- postmaster
- documented
- true
- enumvals
- Unknown
- extra desc
- Unknown
- lang
- en
- max val
- 128
- metadata version
- 18
- min val
- 1
- name
- io_max_combine_limit
- short desc
- Server-wide limit that clamps io_combine_limit.
- source
- pg-settings-source-snapshot
- unit
- 8kB
- vartype
- integer
Definition PG 18
Controls the largest I/O size in operations that combine I/O, and silently limits the user-settable parameter io_combine_limit. This parameter can only be set at server start. If this value is specified without units, it is taken as blocks, that is BLCKSZ bytes, typically 8kB. The maximum possible size depends on the operating system and block size, but is typically 1MB on Unix and 128kB on Windows. The default is 128kB.
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center · PostgreSQL 18 · wiki-repair-20261023:ad633f0fc8a289da2c5152103e71e9f08c7c4f1d8b17bd9a35150aefb4909f9a
Text language: en · wiki-repair-20261023:ad633f0fc8a289da2c5152103e71e9f08c7c4f1d8b17bd9a35150aefb4909f9a