I use awk for monitoring scripts which must run on large scale (>200 node) clusters, because: 1. It is lightweight -- there is no need to load shared libraries

I use awk for monitoring scripts which must run on large scale (>200 node) clusters, because: 1. It is lightweight -- there is no need to load shared libraries, modules, plugins, etc., and it uses less memory than the more general purpose scripting languages do. 2. It comes with BusyBox, so if you have a BusyBox PXE boot environment you can make the AWK scripts work under it, and also work independently of any host OS that gets booted, as long as it's Unix-like. Perl, Python and Ruby are not in Busybox, and their versions can vary a lot across different OS distributions and cluster configurations. AWK avoids this dependency because it's stable and self-contained in one executable file. 3. AWK automatically splits records into fields based on a settable FS, so it makes it very easy to parse things like /proc/stat and /proc/loadavg into $1 $2 $3 ... fields. The code looks nicer and is more compact because of the automatic field variables. 4. The default RS is newline, and AWK is designed to perform actions on records. Most of the scripts I write perform an action upon receiving a newline on their standard input as a trigger. So most of the scripts tend to be of the "BEGIN { } { }" variety -- initialization in the BEGIN section, and then an unconditional action to fire at every newline, such as collecting /proc statistics and reporting them up the cluster hierarchy. AWK is naturally suited for this REPL behavior without needing any boilerplate code.