RFR: 8024826: (s) : Remove alt-rt.jar, used by +AggressiveOps"

David Holmes david.holmes at oracle.com
Tue Sep 17 07:21:01 UTC 2013

Hi Mike,

Looks like there is one test that knows it has to exercise the 
alt-rt.jar version:


  * @run main/othervm Clone
  * @run main/othervm -XX:+AggressiveOpts Clone

but it's harmless to leave the second invocation.

I didn't see anything in JDK or hotspot regression tests that would be 

Once you are ready I will sponsor the hotspot patch for you through 


On 17/09/2013 12:37 PM, David Holmes wrote:
> Reviewed both hotspot and jdk changes.
> Thumbs up and good riddance! :)
> How do you propose to handle the coordination of the push?
> Thanks,
> David
> On 17/09/2013 10:16 AM, Mike Duigou wrote:
>> Hello all;
>> This is a cross-repo patch which disables building and enabling of the
>> alt-rt.jar file. The alt-rt.jar file has been used with the
>> -XX:+AggressiveOpts option (which will be remaining for other
>> optimizations). This jar file formerly contained (closed-source)
>> versions of several JDK classes which were optimized for very specific
>> workloads. The implementations weren't generally applicable and in
>> many cases induced performance drops. In particular since we will not
>> be providing optimized implementations of the Java 8 streams API for
>> the alternate versions of these classes the performance relative to
>> the standard implementations would be poor.
>> Over time we've (largely Alan Bateman) been trying to eliminate this
>> difficult to support feature. With this changeset the alt-rt.jar
>> feature is retired.
>> http://cr.openjdk.java.net/~mduigou/JDK-8024826/0/webrev/
>> Ideally I would like a reviewer for both the HotSpot and JDK repos
>> (could be the same person).
>> Mike

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