Four seconds might not be a long time, but it seems like forever when you are waiting for a page to load. If you are running a commercial website and the user has the perception your site is slow, you might just lose a customer. With the expectation of fast load times, website administrators know that every second (or fraction) counts. If you look closely at your web server environment, you might just find that half the average wait time is unnecessary. But tuning is often a matter of trade-offs – performance improvements sometimes require sacrifice in other areas. Before you make any changes, be sure you understand the implications.

Web server performance is often measured around three common indicators:

• the number of requests served per second;
• site throughput in bytes per seconds;
• the response latency for each new request (including new connections).

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