time java -showversion -cp classes/java/util/Map -Xcomp -XX:+DeoptimizeALot -client Collisions
java version "1.8.0_60-ea-fastdebug"
Java(TM) SE Runtime Environment (build 1.8.0_60-ea-fastdebug-b12)
Java HotSpot(TM) Server VM (build 25.60-b12-fastdebug, mixed mode)
real 13m44.424s
user 12m16.834s
sys 1m35.533s

time java -showversion -cp classes/java/util/Map -Xcomp -XX:+DeoptimizeALot -server Collisions
real 2m5.833s
user 2m5.802s
sys 0m10.932s

Profilers show a lot of String.format calls. Looks like
        for (int i = 0; i < keys.length; i++) {
            check(String.format("insertion: map expected size m%d != i%d", map.size(), i),
                    map.size() == i);
            check(String.format("insertion: put(%s[%d])", keys_desc, i), null == map.put(keys[i], keys[i]));
            check(String.format("insertion: containsKey(%s[%d])", keys_desc, i), map.containsKey(keys[i]));
            check(String.format("insertion: containsValue(%s[%d])", keys_desc, i), map.containsValue(keys[i]));
        }

check() needs to be rewritten to use lazy message formatting.