Linux Ram & Swap memory

Project Notes

This simple but useful plugin is a bash shell script that collects information about the free and used Ram and Swap memory on a Linux box and calculates the relative (percent) values for each. It then compares the two percent values with the two thresholds specified as parameters alerting with a "Warning" state if at least one of the values exceeds the related threshold or with a "Critical" state if both the values exceed them. The relative values for free and used Ram memory are calculated on the base of the memory actaully used by the system itself and by the applications i.e. without the portion of Ram dedicated to the disk I/O blocks (buffers) and to page cache (cache) or shorthly, without the portion of Ram that the system can purge and flush in response of memory pressure. The script makes use of 'bc' , that extends the bash shell capabilities to a full floating point/arbitrary precision calculator. Note: bc normally requires Glibc,ncurses-libs,readline.