mod_logio - Apache HTTP Server Version 2.4









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Apache HTTP Server Version 2.4



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Apache Module mod_logio

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Description:Logging of input and output bytes per request
Status:Extension
Module Identifier:logio_module
Source File:mod_logio.c
Summary


    This module provides the logging of input and output number of
    bytes received/sent per request. The numbers reflect the actual bytes
    as received on the network, which then takes into account the
    headers and bodies of requests and responses. The counting is done
    before SSL/TLS on input and after SSL/TLS on output, so the numbers
    will correctly reflect any changes made by encryption.

    This module requires mod_log_config.

    When KeepAlive connections are used with SSL, the overhead of the SSL
    handshake is reflected in the byte count of the first request on the
    connection.  When per-directory SSL renegotiation occurs, the bytes are associated
    with the request that triggered the renegotiation.


Topics

 Custom Log Formats
Directives

 LogIOTrackTTFB

Bugfix checklisthttpd changelogKnown issuesReport a bugSee also

mod_log_config
Apache Log Files
Comments


Custom Log Formats


    This module adds three new logging directives. The characteristics of the
    request itself are logged by placing "%" directives in
    the format string, which are replaced in the log file by the values as
    follows:

    Format String
        Description
%I
        Bytes received, including request and headers, cannot be
        zero.
%O
        Bytes sent, including headers, cannot be zero.
%S
        Bytes transferred (received and sent), including request and headers,
        cannot be zero. This is the combination of %I and %O.
        Available in Apache 2.4.7 and later
%^FB
        Delay in microseconds between when the request arrived and the
        first byte of the response headers are written.  Only available if 
        LogIOTrackTTFB is set to ON.
        Available in Apache 2.4.13 and later


    Usually, the functionality is used like this:

    
      Combined I/O log format:
      "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\"
      \"%{User-agent}i\" %I %O"
    


LogIOTrackTTFB Directive

Description:Enable tracking of time to first byte (TTFB)
Syntax:LogIOTrackTTFB ON|OFF
Default:LogIOTrackTTFB OFF
Context:server config, virtual host, directory, .htaccess
Override:All
Status:Extension
Module:mod_logio
Compatibility:Apache HTTP Server 2.4.13 and later

    This directive configures whether this module tracks the delay
    between the request being read and the first byte of the response
    headers being written.  The resulting value may be logged with the 
    %^FB format.




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