Information Systems:Analyzing disk usage on Bart

Overview

It should be a habit to reassess disk usage on Bart every once in a while. It helps to understand storage from a big-picture standpoint. This article documents the different methods and tools that can help in such an analysis.

Observations and other notes

For the same BRMS job (or more accurately, for the same list of objects specified by the job to be saved), certain steps seem to take longer for no apparent reason. One possible theory however, is that on fresh media (monthly tapes), writing is faster than on recycled media (daily tapes).

5/31/17   3:42:21  2 blocks processed for sequence 147, volume 000015, on de 
5/31/17   4:09:01  341 objects saved from library CVT454AP.                  

6/01/17   3:40:44  2 blocks processed for sequence 147, volume 001804, on de
6/01/17   3:47:46  341 objects saved from library CVT454AP.