Correct configuration of the MinSpareServers, MaxSpareServers, StartServers, MaxClients, and MaxRequestsPerChild parameters is very important. There are no defaults. If they are too low, you will under-use the system's capabilities. If they are too high, the chances are that the server will bring the machine to its knees.
This article has information and example code for forking a new process, freeing the parent process, detaching the forked process, avoiding zombie processes, a complete fork example, starting a long-running external program, starting a short-running external program, and executing system() or exec() in the right way.
As we have learned in the previous article, sharing memory helps us to save memory with mod_perl, which gives us a huge speed up, but we pay with price of big memory footprint. In this article, we will see other techniques that allow you to save even more memory, such as preloading registry scripts at server startup and initializing CGI.pm.
If your OS supports sharing of memory, you might save a lot of RAM by sharing it between child processes. This will allow you to run more processes and hopefully better satisfy the client, without investing extra money into buying more memory.
The Apache::VMonitor module provides even better monitoring functionality than top(1). It gives all the relevant information top(1) does, plus all the Apache specific information provided by Apache's mod_status module.
In this article we will talk about tools that we need to get armed with before we can start working on the performance of our service. In order to improve performance we need measurement tools. The main tool categories are benchmarking and code profiling.
In the next series of articles we are going to talk about mod_perl performance issues. We will try to look at as many aspects of the mod_perl driven service as possible. Hardware, software, Perl coding and finally the mod_perl specific aspects.
In his next installment of Perl programming basics, Stas Bekman looks at nested subroutines and provides several ways to deal with them successfully.
Anyone interested in using mod_perl with the Apache Web server will need to know the basics of the Perl programming language. In this column, Stas Bekman explains some common pitfalls beginners face when initially tackling Perl.
While installing Apache without root privileges is a very easy task, one should know how to install Perl modules in a non-systemwide location. In this tutorial, Stas Bekman describes how to do just that.
Intimidated by the prospects of configuring mod_perl on your Apache server? Don't be. Getting started with mod_perl shouldn't take you more than 30 minutes, the time it takes to compile and configure the server on a decent machine and get it running. In this column, Stas Bekman explains how to get mod_perl up and running with a minimum of fuss.
One of the most popular Apache modules is mod_perl. We kick off our regular coverage of mod_perl with an overview of the module geared for both true believers and Apache neophytes.
