% cumulative self
time seconds seconds calls name
15.95 0.52 0.52 92467664 camlMutable_rack__has_letter_1031
12.27 0.92 0.40 109589844 caml_apply2
10.74 1.27 0.35 92467664 camlMutable_rack__remove_1035
8.28 1.54 0.27 2478379 camlArray__iteri_1064
7.82 1.80 0.26 32188972 camlMutable_rack__play_1040
3.99 1.93 0.13 64437854 camlTrie__fun_76276
and seems (from the call graphs later down) to be contributing towards the time taken by camlArray_iteri as well, unless I've misunderstood that bit. Is this an actual problem, or just a sign that I've optimised all the obvious bottlenecks already?