Request for reviews (S): 7081842: assert(Compile::current()->unique() < (uint)MaxNodeLimit) failed: Node limit exceeded

Tom Rodriguez tom.rodriguez at
Fri Sep 16 13:48:45 PDT 2011

On Sep 16, 2011, at 12:42 PM, Vladimir Kozlov wrote:

> 7081842: assert(Compile::current()->unique() < (uint)MaxNodeLimit) failed: Node limit exceeded
> URLHammerThread::run (2785 bytes) method's code looks like spaghetti. It has loops, recursive and deep inplining. I see in LogCompilation that up to 70K ideal nodes are created during compilation. And the test passed with -XX:MaxNodeLimit=100000. So we simply missing node limit check in IGVN optimizer which is added.

That looks ok to me.  We may want to reconsider some of these C->unique bailouts since they don't address the number of nodes that are actually live which is the problematic number.  Some things we do generate a lot of garbage nodes that don't contribute to the final code size.  This is good for now though.


> I also did some changes to LogCompilation parser which helped me:
> - added time stamp and nodes count (from parse_done event) to inlining output:
>  @ 147 java.util.ArrayList::get (11 bytes) (end time: 7.1010 nodes: 1127)
> - stat output for phases prints starting and added nodes counts:
>        optimizer 0.0030 545 497
> 	matcher 0.0000 1042 -335
> 	regalloc 0.0060 965 225
> - ignore jvms for eliminate_allocation and eliminate_lock events instead of printing error.
> And I fixed linux/ (which only I use, it seems) to build on x64 linux machines.
> Thanks,
> Vladimir

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