src/test/scripts/functions/lineage/CacheEviction1.dml

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cache_size = ceil($1/(1024*1024)); #in MB
output_size = 8; #8MB
X = rand(rows=1024, cols=1024, sparsity = 1.0, seed=42);
X1 = X;
R = matrix(0, 1024, 1024);
R1 = R;
k = floor((cache_size / output_size));

# Fill the cache with 'exp' and '+' outputs 
for (i in 1:k/2) {
  R = exp(X);
  X = X + 1;
}

# Trigger evictions. LRU evicts half of both 'exp' and '+' results,
# where Weighted scheme evicts all the '+' results to recover
# same amount of memory.
for (i in 1:k/4) {
  R = round(X);
  X = X + 1;
}

# Try to reuse 'exp' and '+' results. LRU keeps evicting
# the remaining half of 'exp' and '+' results from the 1st 
# loop, and in turn fails to reuse any of the instructions, 
# where Weighted scheme keeps evicting the '+'s (from 2nd loop) 
# but able to reuse 'exp's.
for (i in 1:k/4) {
  R1 = exp(X1);
  X1 = X1 + 1;
}

R = R+R1;
write(R, $2, format="text");