kmem_cache_shrink() will explicitly sort the partial lists to put the
partial pages in that order.
Realized that I’d do "echo 1 > /sys/kernel/slab/dentry/shrink” to sort the list explicitly.
After that, the numbers become:
N = 10000 -> diff = 7.1 %
N = 20000 -> diff = 5.7 %
N = 25000 -> diff = 5.4 %
So, expecting ~5-7% difference after shrinking.