GSP
Quick Navigator

Search Site

Linux VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages


Manual Reference Pages  - ACCF_HTTP (9)

NAME

accf_http - buffer incoming connections until a certain complete HTTP requests arrive

CONTENTS

Synopsis
Description
Examples
See Also
History
Authors

SYNOPSIS

options INET options ACCEPT_FILTER_HTTP kldload accf_http

DESCRIPTION

This is a filter to be placed on a socket that will be using accept to receive incoming HTTP connections.

It prevents the application from receiving the connected descriptor via accept until either a full HTTP/1.0 or HTTP/1.1 HEAD or GET request has been buffered by the kernel.

If something other than a HTTP/1.0 or HTTP/1.1 HEAD or GET request is received the kernel will allow the application to receive the connection descriptor via accept.

The utility of accf_http is such that a server will not have to context switch several times before performing the initial parsing of the request. This effectively reduces the amount of required CPU utilization to handle incoming requests by keeping active processes in preforking servers such as Apache low and reducing the size of the file descriptor set that needs to be managed by interfaces such as select, poll or kevent based servers.

The accf_http kernel option is also a module that can be enabled at runtime via kldload(8) if the INET option has been compiled into the kernel.

EXAMPLES

Assuming ACCEPT_FILTER_HTTP has been included in the kernel config file or the accf_http module has been loaded, this will enable the http accept filter on the socket sok.
        struct accept_filter_arg afa;

        bzero(&afa, sizeof(afa));         strcpy(afa.af_name, "httpready");         setsockopt(sok, SOL_SOCKET, SO_ACCEPTFILTER, &afa, sizeof(afa));

SEE ALSO

setsockopt(2), accept_filter(9)

HISTORY

The accept filter mechanism and the accf_http filter were introduced in
.Fx 4.0 .

AUTHORS

This manual page and the filter were written by
.An Alfred Perlstein .
Search for    or go to Top of page |  Section 9 |  Main Index


November 15, 2000 ACCF_HTTP (9)

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.