RFR: 8112: Flamegraph model creation performance improvements [v4]

[Vincent Alexander Beelte]

On Tue, 5 Sep 2023 07:48:11 GMT, Brice Dutheil <bdutheil at openjdk.org> wrote:

>> Vincent Alexander Beelte has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   update copyright header with 2023
>
> core/org.openjdk.jmc.flightrecorder/src/main/java/org/openjdk/jmc/flightrecorder/stacktrace/tree/Node.java line 97:
> 
>> 95: 	public Integer getNodeId() {
>> 96: 		return nodeId;
>> 97: 	}
> 
> **issue:** This is a breaking change. And should be reverted.

Oh, did someone add a call to this? That's unfortunate. Overall this was not that important for performance. It was however also used in the equals method, which I think was wrong. The nodeId is computed using hashing so in theory there might be collisions. Using that for equals would mean Nodes are only compared to be "kind of" equal and not exactly equal.  
I did however also never find a reference where the equals would have been called. I even had a breakpoint in it that never was hit.

-------------

PR Review Comment: https://git.openjdk.org/jmc/pull/502#discussion_r1316221413