Add note on caching effects

lectures/memory-hierarchies/slides.qmd

@@ -172,12 +172,14 @@ new_data = operate_on_data(data=data,
 |                            | Levante (Fixed)   | Laptop (Fixed)    | Levante (Random)  | Laptop (Random)   |
 | -------------------------- | ----------------- | ----------------- | ----------------- | ----------------- |
 | Create data                | 0.56              | 0.23              | 1.66              | 0.88              |
-| Load data                  | 0.76              | 0.88              | 0.76              | 0.92              |
+| Load data                  | 0.76$^*$          | 0.88$^*$          | 0.76$^*$          | 0.92$^*$          |
 | Store data                 | 2.23              | 4.04              | 2.23              | 3.44              |
 | Process data               | 0.76              | 0.38              | 0.76              | 0.37              |
 
 :::{.smaller}
 Time in seconds using a 2 GB numpy array ($128 \times 128 \times 128 \times 128$) either with a fixed number or random number in each entry
+
+$^*$: Lower than one due to caching effects
 :::