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CGI programs run fast in Groupmax World Wide Web

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Recent Common Gateway Interface (CGI) programs tend to be big and slow. Groupmax World Wide Web Version 2 uses strategies so that CGI programs run fast.

• Background: Why are CGIs slow?
  Recent CGI programs are slow for the following reasons:
  
  
  • They are large
    When a CGI program is started, a process is generated on a Web server and the CGI program is loaded. The rapid increase in CGI program size has meant a slower processing speed.
    
    
    
  • Access processings overlap
    When a CGI process is started, the CGI process establishes a connection with the server, processes the login procedure, opens a database, and so on. The CGI process runs extremely slowly if it accesses non-CGI program resources.
  
  
  
• Strategies for running CGI programs faster
  Groupmax World Wide Web uses the following strategies so that CGI programs run faster:
  
  
  1. Separating CGI processes
     In Groupmax World Wide Web, Web server processes are separated into CGI processes and non-CGI processes. This lessens relatively the number of CGI processes started by the Web server. Therefore, CGI processes start faster.
     
  2. Using deamon processes
     Non-CGI processes are asynchronous with the start and end of CGI. Non-CGI processes reside as deamons to manage requests from the browser. The deamon process retains the status of the Mail server connection, the login processing and the database opening processing. This eliminates process duplication and brings about quick response.
  3. Sharing libraries
     Load modules for each process share the same library. Library sharing is achieved by UNIX shared libraries and Windows DLLs. Library sharing reduces the size of each process and forces the library I/O operation to occur only when Groupmax World Wide Web Version 2 is started.
     In fact, no I/O operations will occur since load modules for each CGI process are likely to go to cache. The more CGI processes started, the more likely the load modules go to cache. The size of load modules for each process is:
     
     

     CGI load module	6K
     Deamon process load module	6K
     Management process load module (Resident process that manages deamon processes)	6K
     Shared library	400K

  
  The following figure illustrates the strategies of Groupmax World Wide Web:
  
  
  

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