RFR 8005698 : Handle Frequent HashMap Collisions with Balanced Trees (original) (raw)

Paul Sandoz paul.sandoz at oracle.com
Mon Jun 3 07:56:42 UTC 2013

Hi Brent,

On Jun 3, 2013, at 7:56 AM, Brent Christian <brent.christian at oracle.com> wrote:

I went ahead and created a new webrev. It includes this change, and the comment changes suggested by Alan:

http://cr.openjdk.java.net/~bchristi/8005698/webrev.04/

A minor thing: take it or leave it :-)

In HashMap:

2207 void addEntry(int hash, K key, V value, int bucketIndex, boolean checkIfNeedTree) { 2208 // assert key != null; 2209 if ((size >= threshold) && (null != table[bucketIndex])) { 2210 resize(2 * table.length); 2211 hash = hash(key); 2212 bucketIndex = indexFor(hash, table.length); 2213 } 2214 createEntry(hash, key, value, bucketIndex, checkIfNeedTree); 2215 }

You could re-verify the bucket size if the table is resized rather than in createEntry, since that AFAICT is the only case where conditions after the call to addEntry might change.

Pau.

More information about the core-libs-dev mailing list