mac下Apache添加限速模块mod_bw

官方文档：

Apache2 - Mod_bw v0.7



Author       : Ivan Barrera A. (Bruce)



HomePage     : Http://Ivn.cl/apache & http://bwmod.sf.net



Release Date : 01-09-2005



Status       : Functional. Tested under medium and heavy load.



License      : Licensed under the Apache Software License v2.0

               It must be included as LICENSE in this package.



Platform     : Linux/x86         (Tested with Fedora Core 4, Suse, etc)

               FreeBSD/x86       (Tested on 5.2)

               MacOS X/Ppc x86   (Tested on both platforms)

               Solaris 8/sparc   (Some notes on compile)

               Microsoft Windows (Win XP, Win2003. Others should work)



Notes        : This is a stable version of mod_bw. It works fine with

               almost any MPM (tested with WinNT/prefork/Worker MPM).



Limitations  : This mod doesn't know how fast is the client really 

               downloading a file, so it just divides the bw assigned

               between the users.

               MaxConnections works only for the given scope. (i.e , all 

               will limit maxconnections from all,not per ip or user)





  Especials thanks goes to the "Summer Of Code 2005" program of Google!

 Chris DiBona and all the team, who were helping us out since the beggining.

  Thanks to Ian Holsman and Paul Querna, Mentors from Apache Foundation.





------------------------------------------------------------------------------



Contents :



1 .- Notices

 1.1 - Summer Of Code Program

 1.2 - ChangeLog and TODO



2 .- Installing

 2.1 - Windows

 2.2 - Linux



3 .- Getting it to Work, Directives

 3.1 - BandWidthModule

 3.2 - ForceBandWidthModule

 3.3 - BandWidth

 3.4 - MinBandWidth

 3.5 - LargeFileLimit

 3.6 - BandWidthPacket

 3.7 - BandWidthError

 3.8 - MaxConnection 



4 .- Examples

 4.1 - Misc Examples



5 .- FAQ



------------------------------------------------------------------------------



1.- Notices



 1.1 - Summer Of Code Program :



   Google launch Summer Of Code 2005 program, to motivate the development of

  open source software. Many students around the world signed on the program

  in differents areas/projects. 

   Mine has to do with Bandwidth limiting in current Apache webserver. The 

  main idea behind the program, is to incentivate the development of quality

  open source program, offering a grant in 



------------------------------------------------------------------------------



 1.2 - ChangeLog & TODO :



   This has been moved to the files ChangeLog and TODO. Available on the

  packages and CVS at SourceForge.



------------------------------------------------------------------------------



2.- How To Install :



 2.1 - Windows



   In Windows, you have to download the binary dll from the site (or compile

  one yourself) that matches your apache version, and Install it under modules

  on your apache tree. Then edit httpd.conf, and add the LoadModule sentence.

  If there is no matching binary dll with your version of apache (the latest)

  you can ask me to compile it for you. Post a message in the home site as a

  feature request.



  Example :



    Download mod_bw-2.0.54.dll from the home site, to c:\apache2\modules

    Edit httpd.conf, and add LoadModule bw_module modules/mod_bw-2.0.54.dll

    Restart Apache.



 2.2 - Linux



   Well.. (under *nix) you *have* to compile it..

  It might sound scary, but it's easy. There is an easy way, and the hard way.

  If the easy way doesn't work for you, use the hard way.



  REQUIREMENTS :



   You will need apache2 headers in the include path. In redhat/suse or others

  this mean apache-devel or httpd-devel installed.

   You also need support for SHM in your OS. Usually you will have this.



 - Easy Way :



   For this to work, you MUST have apxs (or apxs2) installed. You might need

  to use it full path (i.e. /usr/sbin/apxs .....). Well, you have to do this :



   apxs -i -a -c mod_bw.c

   or

   apxs2 -i -a -c mod_bw.c



   This will bring out some stuff... nothing to worry (unless you see error)

  If it says ok, then you are ready. Restart apache (service apache restart on

  redhat, mandrake, and others... apachectl restart .. rcapache2 restart or... 

  well, you should know)



  Note On Solaris Users :



   If you got problems compiling it on Solaris, remember to check you have 

  libgcc correctly installed, and the ld_library_path set up correctly. 

   I didnt, so i compiled this way :



   export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

   apxs -i -a -c mod_bw.c -L/usr/local/lib -lgcc_s

               

   And then started apache, and everything worked fine.



  Note On SuSe Users :



   You NEED to have installed apache2 header files (apache2-devel rpm).

  Otherwise you'll get lots of include files error.



 - Hard Way



   If using the easy way, you turned to have some .o files.. you are almost

  done... skip to the part of installing the module.

   Back to the hard way..... you might notice that you dont have apxs,

  dont know why (maybe the dog ate it). Well. try the following (and please

  do it on a newly-fresh created directory for this purpose) :

  (this does not necessarily work on all cases)



    libtool --silent --mode=compile gcc  -g -O2 -pthread    -DLINUX=2 \

        -D_REENTRANT -D_XOPEN_SOURCE=500 -D_BSD_SOURCE -D_SVID_SOURCE \

        -I/usr/include/httpd \

        -I/usr/include/apr-0 -Wall -g\

        -prefer-pic -c mod_bw.c && touch mod_bw.slo





    libtool --silent --mode=link gcc  -g -O2 -pthread    -DLINUX=2 \

        -D_REENTRANT -D_XOPEN_SOURCE=500 -D_BSD_SOURCE -D_SVID_SOURCE \

        -D_GNU_SOURCE -DAP_HAVE_DESIGNATED_INITIALIZER \

        -I/usr/include/httpd \

        -I/usr/include/apr-0 -Wall -g\

        -export-dynamic -o mod_bw.la  -rpath /usr/lib/httpd/modules \

        -module -avoid-version  mod_bw.lo



    (this cleans some unneeded files)

    rm -rf *.a *.la *.lo *.slo *.o *.loT

    mv .libs/*.so .

    rm -rf .libs



    Note that you need to know where are your httpd and apr includes.

    (dont ask me where they are.. you are supossed to know)

    If this worked... we are good to install the module.



   * Installing the module (hey.. this is part of the hard way)



    Ok, either if the easy way didnt install the mod, or if you did the

   hard way, now you must install the module by hand.

    Is easy as copying the file (usually mod_bw.so) to the apache

   modules directory (usually /etc/httpd/modules or 

   /usr/local/libexec/apache2/) and then adding the following line at

   httpd.conf (better of if you add it at the last part of all LoadModule

   sentences) :



    LoadModule bw_module mod_bw.so



    Please, take a look at the other LoadModule sentences. You may need

   to add a path before the .so file. 

   (i.e LoadModule bw_module libexec/apache2/mod_bw.so)







  If you didn't manage to get it installed, drop me a letter. But please

 be sure you tried everything. Sometimes the simplest way, is the better.

------------------------------------------------------------------------------



3.- Getting it to Work :





  Ok.. this is the most confusing part. (yeh, most of us think the installing

 part is the hardest xD )



  This mod, is able to limit bandwidth usage on every virtual host or

 directory. htaccess files are not supported yet, cause i've been having some

 serious segfaults when implementing it.



 * Configuration Directives

 *****************************************************************************



 3.1 - BandWidthModule [On|Off]



    You need to set this to On, for the mod to work.. By default, the mod is

   disabled, and wont limit anything.



   Example :

              BandWidthModule On



 3.2 - ForceBandWidthModule [On|Off]

 

    By default, the mod wont catch every request.

    If you enable it, every request will be processed by the mod.

   

   Example :

              (normal use)

              AddOutputFilterByType MOD_BW text/html text/plain



              (enabling Force)

              ForceBandWidthModule On

 



 3.3 - BandWidth [From] [bytes/s]



    This takes 2 parameters. From is the origin of the connections. It could

   be a full host, part of a domain, an ip address, a network mask (i.e

   192.168.0.0/24 or 192.168.0.0/255.255.255.0) or all.

    The second parameter indicates the total speed available to the Origin.

    If speed is 0, there is no limit.



   Example :

            BandWidth localhost 10240

            BandWidth 192.168.218.5 0



            ( Order is relevant. First entries have precedence )



 3.4 - MinBandWidth [From] [bytes/s]



    This takes 2 parameters. From is the origin of the connections. It could

   be a full host, part of a domain, an ip address, a network mask (i.e

   192.168.0.0/24 or 192.168.0.0/255.255.255.0) or all.

    The second parameter indicates the minimun speed each client will have.

   What does this mean ? If you have a total of 100kbytes speed, and you put

   MinBandWidth at 50kbytes, it doesnt matter how many clients you have, all

   of them will have at minimun 50kbytes of total speed to download.

    If speed is 0, you will be using the default minimun (256 bytes/s).

    There is a special value of -1. This value means that each client, will

   have a top speed determined by the BandWidth directive. See the examples.



   Examples :

              BandWidth    all 102400

              MinBandWidth all 50000

 

             The example above, will have a top speed of 100kb for the 1º

            client. If more clients come, it will be splitted accordingly but

            everyone will have at least 50kb (even if you have 50 clients)



              BandWidth    all 50000

              MinBandWidth all -1



             This example, makes everyone have 50kb as top speed.



 3.5 - LargeFileLimit [Type] [Minimum Size] [bytes/s]



    Type, is the last part of a file, or * for all. You can use .tgz to match 

   only tar-compressed files, .avi to match video files, or * to match all.

    Minimum Size, is the size (in kbytes) of the file, to be matched. That way

   you can match huge video files that hog your bandwidth.

    The last parameter... is obvious. The speed allowed.



   Example :

             LargeFileLimit .avi 500 10240



             This limits .avi files over (or equal to) 500kb to 10kbytes/s



 3.6 - BandWidthPacket [Size]



    Probably you never need to touch this. It defaults to 8192 which is good

   for almost any speed.

    It must be a size between 1024 and 131072. A Small packet will cause the

   top speed to be lower, and the mod using more time splitting. If you use

   a Size too big, the mod will adjust it to lower speeds.



 3.7 - BandWidthError [Error]



    This directives is useful to deliver a personalized error code.

    At default, when maxconnections is reached, the mod will issue a 503 

   HTTP_SERVICE_UNAVAILABLE code. For some users, it is annoying to have an

   error message, and dont knowing why. You could use an ErrorDocument to 

   point error 503 to a page explaining that you are under a heavy load of

   connections, but sometimes 503 isn't issued by the mod.

    So, with this directive, you can set the error code to return when

   maxconnections is reached. You can use any error code between 300 and 599.

   Please note, that some of the error codes are already used, so before using

   any number, take a look to a list of the codes (search for http error codes

   in google). 

    When testing, i've used the error code 510, which hasn't been defined yet.



    And Example, with Personalized Error Page :



      ErrorDocument 510 /errors/maxconexceeded.html

      BandWidthError 510



    Note : Sometimes, the personalized page didn't appear. I'm not sure, but

          in many cases, it got fixed, by making the page size over 1024bytes.

           Anyways, if you need help using ErrorDocument, refer to the apache

          Documentation.

 

 3.8 - MaxConnection [From] [Max]



    This takes 2 parameters. From is the origin of the connections. It could

   be a full host, part of a domain, an ip address, a network mask (i.e

   192.168.0.0/24 or 192.168.0.0/255.255.255.0) or all.

    The second parameter, is the max connections allowed from the origin. Any

   connection over Max, will get a 503 Service Temporarily Unavailable



    There is a catch. You NEED to have a BandWidth limit for the same origin.

   It doesnt need to be a low limit. You can use an unlimited setting.

    You might wonder why. It's because im using them same memory space of the

   bandwidth limit, to count the connections, so i can save memory space.

    If you dont put a BandWidth using the same origin, MaxConnections will be

   ignored.



   Example :

              BandWidth all 0

              MaxConnection all 20

    or

              BandWidth all 0

              BandWidth 192.168.0.0/24 10240

              MaxConnection all 20

              MaxConnection 192.168.0.0/24 5





  Please, rememeber that every speed, will depend mostly on your connection.

 You cant get more speed if you dont have it.



  Remember also.. if you dont follow the instructions, and get some weird 

 results, recheck your config before sending me an email.



------------------------------------------------------------------------------



4.- Examples



  4.1 - Misc examples



    Limit every user to a max of 10Kb/s on a vhost :



    <Virtualhost *>

      BandwidthModule On

      ForceBandWidthModule On

      Bandwidth all 10240

      MinBandwidth all -1

      Servername www.example.com

    </Virtualhost>





    Limit al internal users (lan) to 1000 kb/s with a minimum of 50kb/s , and 

  files greater than 500kb to 50kb/s.



    <Virtualhost *>

      BandwidthModule On

      ForceBandWidthModule On

      Bandwidth all 1024000

      MinBandwidth all 50000

      LargeFileLimit * 500 50000

      Servername www.example.com

    </Virtualhost>





    Limit avi and mpg extensions to 20kb/s.



    <Virtualhost *>

      BandwidthModule On

      ForceBandWidthModule On

      LargeFileLimit .avi 1 20000

      LargeFileLimit .mpg 1 20000

      Servername www.example.com

    </Virtualhost>





    Using it the "right" way, with output filter by mime type (for text) 

  to 5kb/s:

    

    <Virtualhost *>

      BandwidthModule On

      AddOutputFilterByType MOD_BW text/html text/plain

      Bandwidth all 5000

      Servername www.example.com 

    </Virtualhost>





    If you need help on doing more complex setup, you could post it in sf.net 

  forums.



------------------------------------------------------------------------------



5.- FAQ



(No particular order)



1.- Why should i use mod_bw ?



    If you want to restrict the top speed a site is able to use, or limit the

  max connections allowed per site, or just to try the mod.

    Some people told me, they use it primarily to stop small sites hogging 

  all the bandwidth when serving video, images, or other content.



2.- How do i ... ?



    First, read the documentation. it is pretty straightforward to use.

  If you can't make it work, or if you want to ask for a feature, visit the

  home site, and post a request. Remember to read the documentation and the

  faq. If the request is already posted, i'll just delete the duplicates.



3.- What's the difference with mod_bwshare, mod_throttle, etc ?



    The main difference, is that this mod, is aimed to the Apache 2 API.

  Some other differences, is, how this mod works, and the directives it 

  implements.

    I took some ideas from other mods, as the shared memory implementation

  (mod_bandwidth2 from Tim Verhoeven). Most of the directives, are in origin

  from mod_bandiwdth for apache 1.



4.- How does it works ?



    The mod, will set a shared memory holding all of the configuration you

  make. In this space, it will also, keep a "count" of the info currently

  using (as current connections, bw used, time, and bytes sent).

    When you assign a bw limit, the mod will "split" the data, and will send

  it piece by piece, with a small delay between pieces. The delay will be

  adjusted so at least 1 piece is sent in a second, thus eviting browser

  timeout.

    If there are two or more clients downloading from the same vhost, the

  limit will be "splitted" too. So, if you have a bw limit of 16Kb and two

  clients, each one will have 8Kb to download. You can also set a fixed 

  download rate, so each client will have a fixed maximun download rate.

    This is a simple explanation of how this works. Take a look at the code

  if you want to know more about it.



5.- Can you make it do ... ? 



    Post a request for a feature in the home site. I'll respond there.



6.- Can you make mod_bw work for ... ?



    See question 5. Anyways, if i dont own (or have access) to the hardware

  needed, i won't be able to help you.



7.- I'm having some trouble in windows ... 



    I cannot support windows in an official way. I do not own a licensed copy

  of Windows, or Visual C.

    Anyways, post your problem in the home site. 



8.- The mod is not limiting certain Directory



    Ok... first, read the documentation. Then the FAQ. If it isn't working,

  then look if you have defined correctly the limits within that directory.

    If you have a limit in a vhost, and inside the vhost, a directory with

  another limit, a new context with the configs of the directory is created,

  and only have the configurations you added there. 



  In example :



  <VirtualHost *>

    BandWidthModule On

    BandWidth all 16384

    LargeFileLimit * 500 4096

    <Directory />

      LargeFileLimit * 100 1024

    </Directory>



  This wont limit Directory / to 16384. The Directory wont "inherit" the

 settings from the vhost if you use some of the mod's directives.





------------------------------------------------------------------------------

  



 Ivan Barrera A. 

 Ivn Systems Software                                      -([email protected])-

　　

我的步骤：

1.下载并解压:

http://ivn.cl/files/source/mod_bw-0.92.tgz

2.安装：

apxs -c -i -a mod_bw.c

出现N多蛋疼的错误：

　　①由于HomeBrew与新的OS X 10.9某些环境变量的问题，apxs命令在安装中用到cc编译命令，但是HomeBrew的cc指向/Applications/Xcode.app/Contents/Developer/Toolchains/OS X10.9.xctoolchain/usr/bin/cc，而新版的OSX10.9对应的Xcode5的cc命令在这里：/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin，这样就找不到命令了。

　　我的解决办法是修改了/usr/share/apr-1/build-1/apr_rules.mk和/usr/share/apr-1/build-1/libtool里边的OS X10.9为XcodeDefault。

但是还是找不到这个命令，报错一样，路径没有改过来，后来修改了环境变量，参考 上一篇文章 《Xcode开启gcc/g++》。

还是没有解决：最终重装了HomeBrew才解决这个异常。参考 《Mac OS X下HomeBrew安装卸载》

 

　　②遇到未识别的tag错误：命令前加标志，最终命令为：LTFLAGS=--tag=cc apxs -c -i -a mod_bw.c

　　③编译完mod_bw.so在这里mod_bw-0.92/.libs/mod_bw.so（.libs是隐藏文件夹，参考 《mac显示隐藏文件夹》），移动到Apache库目录的时候权限不足，失败。自己复制过去我用的是Mac OS X自带的Apache所以复制到/usr/libexec/apache2/mod_bw.so,这样算是安装了这个限速模块了。

 

3.配置：

　　①在httpd.conf中开启mod_bw模块：/private/etc/apache2/httpd.conf=====>去掉LoadModule bw_module          libexec/apache2/mod_bw.so最前面的#号,保存即可。（因为需要系统权限所以用sudo vi /private/etc/apache2/httpd.conf修改比较方便）.

　　②每个网站（virtual host）添加限速功能：

　　httpd.conf中对应目录添加红色代码（可根据自己需要修改）：

　　

<Directory "/Library/WebServer/Documents">

    #

    # Possible values for the Options directive are "None", "All",

    # or any combination of:

    #   Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews

    #

    # Note that "MultiViews" must be named *explicitly* --- "Options All"

    # doesn't give it to you.

    #

    # The Options directive is both complicated and important.  Please see

    # http://httpd.apache.org/docs/2.2/mod/core.html#options

    # for more information.

    #

    Options Indexes FollowSymLinks MultiViews



    #

    # AllowOverride controls what directives may be placed in .htaccess files.

    # It can be "All", "None", or any combination of the keywords:

    #   Options FileInfo AuthConfig Limit

    #

    AllowOverride None



    #

    # Controls who can get stuff from this server.

    #

    Order allow,deny

    Allow from all



    # start the bandwidth limit

    BandWidthModule On 

    ForceBandWidthModule On

    #开放20KB对localhost使用，可以用all指向所有的

    Bandwidth localhost 20480

    #每个Connection最小带宽为2K

    MinBandwidth all 2048



</Directory>

　　重启apache就可以模拟限速下载了：sudo apachectl restart