after.txt

insert (small, no index)....................................6776
insert (medium, no index)...................................1459
insert (large, no index)....................................1038
insert (small, indexed).....................................5734
insert (medium, indexed)....................................5695
insert (large, indexed).....................................1022
batch insert (small, no index)..............................20394
batch insert (medium, no index).............................14569
batch insert (large, no index)..............................906
find_one (small, no index)..................................831
find_one (medium, no index).................................671
find_one (large, no index)..................................533
find_one (small, indexed)...................................1970
find_one (medium, indexed)..................................1898
find_one (large, indexed)...................................894
find (small, no index)......................................509
find (medium, no index).....................................391
find (large, no index)......................................333
find (small, indexed).......................................1696
find (medium, indexed)......................................1653
find (large, indexed).......................................763
find range (small, indexed).................................113
find range (medium, indexed)................................81
find range (large, indexed).................................11

analysis.txt

The improvement in Mongo::ObjectID#generate seems marginal, but still avoids 3 Array#pack operations.
The big savings are when converting large objects because it dramatically reduces the number of times
Array#pack+Integer#to_int is called.

before.txt

insert (small, no index)....................................4920
insert (medium, no index)...................................1605
insert (large, no index)....................................288
insert (small, indexed).....................................4346
insert (medium, indexed)....................................3733
insert (large, indexed).....................................288
batch insert (small, no index)..............................16285
batch insert (medium, no index).............................8619
batch insert (large, no index)..............................286
find_one (small, no index)..................................810
find_one (medium, no index).................................606
find_one (large, no index)..................................197
find_one (small, indexed)...................................1546
find_one (medium, indexed)..................................1337
find_one (large, indexed)...................................225
find (small, no index)......................................415
find (medium, no index).....................................330
find (large, no index)......................................153
find (small, indexed).......................................1400
find (medium, indexed)......................................1272
find (large, indexed).......................................215
find range (small, indexed).................................88
find range (medium, indexed)................................57
find range (large, indexed).................................2