Achieving high performance from a web application is critical. This is because there are a lot of criteria that determine performance. The following are some of the standard parameters typically considered:
Web server response time
Throughput
User satisfaction — Apdex score
Concurrency — Requests Per Minute (RPM)
Network latency and end-user response
These are only a few parameters that are used for determining web application performance.
Note
Usually if the web server response is under 500 ms and the end-user response is under three seconds, your application is considered to be in good shape.
Web server response is the time taken for any server to respond to an HTTP request. Typically, if we look at the log files that are generated for a Rails application, it gives us some idea about this. The log files would contain something like the following:
Started GET "/books" for 127.0.0.1 at 2012-1-28 23:11:35 +0530
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Completed...