Web Server - Apache (Counters & Tuning Tips)

What is Web-Server?

A Web server is a system that delivers content or services to end users over the Internet. A Web server consists of a physical server, server operating system (OS) and software used to facilitate HTTP communication. A Web server is also known as an Internet server. Every Web server has an IP address and possibly a domain name. A Web server is a program that uses HTTP (Hypertext Transfer Protocol) to serve the files that form Web pages to users, in response to their requests, which are forwarded by their computers' HTTP clients. Leading Web servers include Apache, Microsoft's Internet Information Server (IIS) and ASP.net.

Apache Web Server Counters:

1. CPULoad: The current percentage of CPU consumed by the Apache server

2. ReqPerSec: The number of requests per second (a.k.a. hits per second)

3. BytesPerSec: The number of bytes transferred per second

4. BytesPerReq: The number of bytes transferred per request

5. BusyWorkers: Number of active threads serving requests

6. IdleWorkers: Number of inactive/idle threads

Tuning Tips:

Below are some tuning tips for Apache servers.

1. HostnameLookups directive should be off (off by default).

2. KeepAlive directive should be on (on by default).

3. KeepAliveTimeout directive should be in the limit (say 15 seconds). It represents the number of seconds. Apache will wait for a subsequent request before closing a connection. The higher the timeout, the more server threads will be kept occupied waiting on connections with idle clients.

4. Avoid using .htaccess files. The use of .htaccess files can be disabled completely by setting the AllowOverride directive to none.

5. It is recommended to unload unused modules in order to optimize memory utilization.

6. The MaxKeepAliveRequests directive specifies the maximum number of child processes that will be created to serve requests and limits the number of simultaneous requests that will be served. Any connection attempts that are over the MaxClients limit will normally be queued, up to a number based on the ListenBacklog directive. You should set this to the maximum number of clients that your environment can manage without experiencing throughput degradation or a prohibitive increase of the response time.

Information source: https://www.microfocus.com/media/documentation/loadrunner_and_performance_center_document.pdf

Related Topic:

• Important Server Counters
• Windows Server Counters
• Web Server - ASP (Tuning Tips)
• Understand - Service Time, Queue Time and Response Time