eric-maynard opened a new pull request, #21:
URL: https://github.com/apache/polaris-tools/pull/21

   This implements a new scenario, `WeightedWorkloadOnTreeDataset`, that 
supports the configuration of multiple **distributions** over which to weight 
reads & writes against the catalog. 
   
   Compared with `ReadUpdateTreeDataset`, this allows us to understand how 
performance changes when reads or writes frequently hit the same tables.
   
   ### Sampling
   
   The distributions are defined in the config file like so:
   ```
       # Distributions for readers
       # Each distribution will have `count` threads assigned to it
       # mean / variance describe the properties of the normal distribution
       # Readers will read a random table in the table space based on sampling
       # Default: [{ count = 8, mean = 0.3, variance = 0.0278 }]
       readers = [
         { count = 8, mean = 0.3, variance = 0.0278 }
       ]
   ```
   
   `count` is simply the number of threads which will sample from the 
distribution, while `mean` and `variance` describe the Gaussian distribution to 
sample from. These values are generally expected to fall between 0 and 1.0 and 
when they don't the distribution will be repeatedly **resampled**.
   
   For an extreme example, refer to the following:
   <img width="400" alt="Screenshot 2025-04-30 at 1 27 43 AM" 
src="https://github.com/user-attachments/assets/d77e98f1-7a94-463d-be82-0c47bbda92a1";
 />
   
   In this case, about 50% of samples should fall below 0.0 and therefore be 
resampled.
   
   Once a value between 0 and 1 is obtained, this is mapped to a table, where 
1.0 is the highest table (e.g. T_2048) in the tree dataset and 0.0 is T_0.


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