Persistent Feeders in TM1 – Speed-Up Model Restarts
Do you have a large TM1 model that takes forever to load when it is restarted? Do you have complex feeders or large feeder files in your model? If you do, then you will probably benefit from enabling Persistent Feeders in your model.
What are Feeders?
Feeders are a setting in TM1 rules that enable a cell in a cube to be calculated. They set a flag in a cube that, in essence, activates that cell. Then when there is a rule that calculates that cell, it will work. Feeders are stored in a file in your model’s data folder. When the model restarts, they are regenerated automatically, except when we have persistent feeders.
Why do we have Feeders?
Feeders are the secret sauce behind the massive power of TM1. If you imagine a cube with 5 dimensions of just ten elements in each dimension, that is 10x10x10x10x10 = 100,000 cells. Using feeders, only those cells that need to be calculated will be enabled – usually nowhere near the total number of cells in a cube.
What are Persistent Feeders?
Persistent Feeders, as the name suggests, “persist” when the model is restarted, rather than being regenerated. So if you have a large or complex feeder, it will be read from disk upon restart, rather than being recreated, as is the default.
How to Enable Persistent Feeders
Open your model’s tm1s.cfg file and add or change the parameter called PersistentFeeders to be true. It should look like this:
This will then force feeders to be loaded from disk upon model restart.
Note also that if there is any problem with the feeders file when a model is restarted, TM1 will force the regeneration of the feeders file during the restart process.