[aarch64-port-dev ] jdk11 fastdebug seems to have slowed down.

[Dave Nuechterlein]

I have traced the difference down to src/hotspot/share/code/compiledMethod.hpp.  The PcDescContainer::find_pc_desc_internal seems to be doing a lot of searching of long lists.

This obviously might not be a Aarch64 port issue, but rather a hotspot issue.  If anyone here has any experience with the whole PcDescContainer, or has seen fastdebug execution times escalating, I would appreciate getting any kind of help.  The PcDescContainer appears to be some way for a method to understand its calling hierarchy.

Thanks,
Dave


-----Original Message-----
From: aarch64-port-dev <aarch64-port-dev-bounces at openjdk.java.net> On Behalf Of Dave Nuechterlein
Sent: Friday, July 27, 2018 3:18 PM
To: aarch64-port-dev at openjdk.java.net
Subject: [aarch64-port-dev ] jdk11 fastdebug seems to have slowed down.

I pulled a jdk11 tree two days ago, and built both the release and fastdebug versions (--enable-debug).  Running specjbb 2015 v1.01, I get about the same result for HBIR that I have in the past on the release version.  The fastdebug posts a score 4.8x slower than the release.  I have never seen that kind of slowdown before.  I was seeing about 1.2x drop.  Anyone else seen fastedbug slow dramatically, or have an idea of what might have changed?  I pulled/updated again today, and it is about the same.

Dave