System.identityHashCode performance

Tom Hawtin Thomas.Hawtin at Sun.COM
Tue Sep 22 11:35:36 UTC 2009

Janda Martin wrote:
> I would like to ask about any plans of speed improvements to "System.identityHashCode" or "IdentityHashMap"
> I use EclipseLink and it uses IdentityHashMap for storing entities and their clones.
> In my case System.identityHashCode consumes 54% of time during insert data to database. There are lots of other project using IdentityHashMap and identityHashCode.

CR 6378256 seems to cover this for the client/C1 compiler. Presumably 
the server/C2 compiler already intrinsifies the method. It's been in 
"fix understood" for a couple of years...

Tom Hawtin

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