With the large 16MB LLC, it takes a consid­erable amount of time for applications to load their work­ing sets in the cache, thus the performance improvement increases from 15ms to 30ms timeslice length due to the in­creased amount of time to amortize LLC cold start cache misses.
beyond 30-45ms timeslices, there is only marginal performance improvement since the applications working set data is then loaded in the LLC and the cold start penalty amortized.