# ioBufferSize

Size of the buffer used to writing output data.

This parameter applies to omfile: File Output Module.

Name:

  ioBufferSize

Scope:

  action

Type:

  size

Default:

  action=4 KiB

Required?:

  no

Introduced:

  at least 5.x, possibly earlier

## Description

Size of the buffer used to writing output data. The larger the buffer, the potentially better performance is. The default of 4k is quite conservative, it is useful to go up to 64k, and 128k if you used gzip compression (then, even higher sizes may make sense)

## Action usage

    action(type="omfile" ioBufferSize="...")

### Legacy names (for reference)

Historic names/directives for compatibility. Do not use in new configs.

- $OMFileIOBufferSize — maps to ioBufferSize (status: legacy)

## See also

See also omfile: File Output Module.

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