Cost Rollup - Estimated processing time doesn't match the realistic processing time
When running the Cost Rollup, there is an option to show the progress. This option also provides an estimated time for completion. We've found that in some cases this estimate can be very different than the actual processing time. We've also found that these estimates can be very difficult to provide, accurately.
Currently, we recommend not showing the progress bar unless there is a need. Just showing the progress causes the Rollup process to be slower. In the future, we plan to revamp our approach to the Cost Rollup design, which will negate the need for a progress bar at all.