Overview of new features in Apache HTTP Server 2.4

Core Enhancements

Loadable MPMs

Multiple MPMs can now be built as loadable modules at compile time. The MPM of choice can be configured at run time.

Event MPM

The Event MPM is no longer experimental but is now fully supported.

Asynchronous support

Better support for asynchronous read/write for supporting MPMs and platforms.

Per-module and per-directory LogLevel configuration

The LogLevel can now be configured per module and per directory. New levels trace1 to trace8 have been added above the debug log level.

Per-request configuration sections

, , and sections can be used to set the configuration based on per-request criteria.

General-purpose expression parser

A new expression parser allows to specify complex conditions using a common syntax in directives like SetEnvIfExpr, RewriteCond, Header, , and others.

KeepAliveTimeout in milliseconds

It is now possible to specify KeepAliveTimeout in milliseconds.

NameVirtualHost directive

No longer needed and is now deprecated.

Override Configuration

The new AllowOverrideList directive allows more fine grained control which directives are allowed in .htaccess files.

Config file variables

It is now possible to Define variables in the configuration, allowing a clearer representation if the same value is used at many places in the configuration.

Reduced memory usage

Despite many new features, 2.4.x tends to use less memory than 2.2.x.