Update memory mountain slides and exercise

lectures/memory-hierarchies/slides.qmd

@@ -446,11 +446,18 @@ Based on a typical Levante node (AMD EPYC 7763)
 
 ## Memory Mountain (1/2)
 
-Describe what is done
+:::{.smaller}
+
+Code for program contained in "Computer Systems":
+
+<https://csapp.cs.cmu.edu/3e/mountain.tar>
+
+:::
 
- - Influence of block size
- - Influence of stride
- - Measurements done on Levante compute node
+ - Process a representative amount of data
+ - Use `stride` between array elements to control spatial locality
+ - Use `size` of array to control temporal locality
+ - Also warm up the cache before the actual measurements
 
 
 
@@ -469,8 +476,10 @@ $\approx$ Factor 20 between best and worst access
 
 ## Hands-On {.handson}
 
- - Either example with optimal and sub-optimal memory access, i.e. cache blocking (see `nproma`)
- - Or OpenMP reduction (hand implementation), reference/continuation from parallelism lecture?!
+1. Download and extract the C source code of the memory mountain program linked in the from previous slides
+2. Compile the program and run it on your PC or a Levante compute node
+3. Which factor do you get between best and worst performance?
+4. (optional) Visualize your results