[NEW BUG]: Reduce allocations in sun.reflect.annotation.AnnotationInvocationHandler.invoke() (original) (raw)

Claes Redestad claes.redestad at oracle.com
Mon Nov 28 13:35:24 UTC 2016

Hi,

for general guidelines on contributing: http://openjdk.java.net/contribute/ [1]

As for the patch I think it looks good, but out of curiosity I wonder if you have any numbers on how much allocations you see in these methods and how much this patch helps? A non-escaping clone like this should typically be possible for the JIT to escape entirely, but if that's not happening I don't see why we should be opposed to a simple optimization like this.

Once changes suggested by Peter Levart is pushed[2] we could improve this further by using LangReflectAccess.getExecutableSharedParameterTypes, which will get direct access to the array and thus help the slow case too (if that matters).

Is it perhaps worth changing ordering around while we're at it?

if (parameterCount == 1 && member.equals("equals") && ...

Thanks!

/Claes

[1] Someone correct me if I'm wrong, but I've heard somewhere that for a trivial patch contribution like this signing an OCA is not strictly necessary. Regardless, providing the patch attached or inline is enough to allow us to sponsor it for you.

[2] http://mail.openjdk.java.net/pipermail/core-libs-dev/2016-October/043932.html http://cr.openjdk.java.net/~plevart/jdk9-dev/Class.getMethods.new/webrev.07/

On 2016-11-28 13:57, Christoph Dreis wrote:

Hey,

I'm new to the OpenJDK and not sure (yet) how the procedure especially for new bugs/enhancement is. So I apologise upfront if I made any mistakes. I'm working mostly with the Spring-Framework/Spring-Boot in my current projects. In these frameworks a lot of dynamic proxying can happen. Recently, I noticed that the JDK in versions 8 up to the current snapshots produces some allocations coming from sun.reflect.annotation.AnnotationInvocationHandler.invoke() we could avoid in the majority of cases. Only the check for equality needs the actual parameter types - all other cases only need the parameter count which JDK 8 luckily provides with Method.getParameterCount(). What about changing the current behaviour to something like my attached proposal? I'd be happy if someone is willing to sponsor this change. Again - if I made any mistakes here, please let me know for the next time. Cheers, Christoph Dreis ================================ Reduce allocations in sun.reflect.annotation.AnnotationInvocationHandler.invoke() diff -r ba70dcd8de76 -r 86bbc5442c1d src/java.base/share/classes/sun/reflect/annotation/AnnotationInvocationHandl er.java --- a/src/java.base/share/classes/sun/reflect/annotation/AnnotationInvocationHan dler.java Fri Nov 11 13:11:27 2016 +0000 +++ b/src/java.base/share/classes/sun/reflect/annotation/AnnotationInvocationHan dler.java Mon Nov 14 19:04:33 2016 +0100 @@ -57,13 +57,13 @@ public Object invoke(Object proxy, Method method, Object[] args) { String member = method.getName(); - Class<?>[] paramTypes = method.getParameterTypes(); + int parameterCount = method.getParameterCount(); // Handle Object and Annotation methods - if (member.equals("equals") && paramTypes.length == 1 && - paramTypes[0] == Object.class) + if (member.equals("equals") && parameterCount == 1 && + method.getParameterTypes()[0] == Object.class) return equalsImpl(proxy, args[0]); - if (paramTypes.length != 0) + if (parameterCount != 0) throw new AssertionError("Too many parameters for an annotation method"); switch(member) {

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