mod_buffer - Apache HTTP Server Version 2.4









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Apache HTTP Server Version 2.4



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Apache Module mod_buffer

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Description:Support for request buffering
Status:Extension
Module Identifier:buffer_module
Source File:mod_buffer.c
Compatibility:Available in Apache 2.3 and later
Summary

    This module provides the ability to buffer the input and output
    filter stacks.

    Under certain circumstances, content generators might create
    content in small chunks. In order to promote memory reuse, in
    memory chunks are always 8k in size, regardless of the size of the
    chunk itself. When many small chunks are generated by a request,
    this can create a large memory footprint while the request is
    being processed, and an unnecessarily large amount of data on the
    wire. The addition of a buffer collapses the response into the
    fewest chunks possible.

    When httpd is used in front of an expensive content generator,
    buffering the response may allow the backend to complete
    processing and release resources sooner, depending on how the
    backend is designed.

    The buffer filter may be added to either the input or the
    output filter stacks, as appropriate, using the
    SetInputFilter,
    SetOutputFilter,
    AddOutputFilter or
    AddOutputFilterByType directives.

      Using buffer with mod_includeAddOutputFilterByType INCLUDES;BUFFER text/html


    The buffer filters read the request/response into
        RAM and then repack the request/response into the fewest memory
        buckets possible, at the cost of CPU time. When the request/response
        is already efficiently packed, buffering the request/response could
        cause the request/response to be slower than not using a buffer at
        all. These filters should be used with care, and only where
        necessary.


Directives

 BufferSize

Bugfix checklisthttpd changelogKnown issuesReport a bugSee also

Filters
Comments


BufferSize Directive

Description:Maximum size in bytes to buffer by the buffer filter
Syntax:BufferSize integer
Default:BufferSize 131072
Context:server config, virtual host, directory, .htaccess
Status:Extension
Module:mod_buffer

    The BufferSize
    directive specifies the amount of data in bytes that will be
    buffered before being read from or written to each request.
    The default is 128 kilobytes.




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