Lead Image © Gennadiy Poznyakov, 123RF.com

Visualizing log and other data

Painting by Numbers

Article from ADMIN 17/2013

By Tim Schürmann

Logfiles contain extremely useful traces of everyday events – if only they weren't so boring. Fortunately, special tools help you generate and even animate colorful, easily interpretable graphics.

If you want to evaluate your logfiles, you are likely to turn to a log viewing tool. In the simplest case, log viewers show you the data in tabular form; more sophisticated programs at least give a small bar, pie, or line chart. However, these graphics are mostly just a snapshot. Being able to trace the capacity of a web server over a period of time would be much more enlightening.

Gource, code_swarm, Logstalgia, Fudgie, Conky, and cpuplayer handle technical visualizations. Each of the six programs specializes in a very specific field of application. For example, Logstalgia animates access logs for a web server, whereas Gource reveals changes in a version control system. Each tool also uses a slightly different visualization format – although dots and circles seem to be pretty popular.

All candidates are designed for standard desktop PCs and are not intended for direct use on a (virtual) server. With a few exceptions, the admin has to transfer the data to be analyzed to his or her own computer. Logstalgia and Gource output their graphics via the OpenGL interface.

Gource

The content of a version control system looks like a colorful tree – at least if the admin lets Gource [1] loose on it. When you launch Gource, you initially see small colorful balls, each corresponding to a (source) file. Their colors depend on the file type; C++ files, for example, are blue. All files located in a common directory are collected in a small heap. Gource draws the directory structure as thin white branches (Figure 1).

...

Use Express-Checkout link below to read the full article (PDF).