Great news: Lucene 9.4 (optionally) uses mapped MemorySegments when JDK 19 is detected

[Maurizio Cimadamore]

That is great and exciting news! Thanks for all your hard work keeping 
up with the API changes.

Of course it would be great to hear how it works for you guys, so, 
should there be any odd performance issues, please give us a shout :-)

Cheers
Maurizio



On 29/09/2022 16:46, Uwe Schindler wrote:
> Hi all, hi Maurizio,
>
> I just wanted to inform you that after Java 19 was released we jumped 
> on the train and we will most likely release Apache Lucene 9.4 already 
> tomorrow with support for project Panama. Users can run Lucene-based 
> applications with "--enable-preview" and all should work automatically 
> thanks to MR-JAR.
>
> The PR was merged on Monday after Eclipse Adoptium made the JDK 19 
> builds available, so Gradle was able to pick them up to compile the 
> MR-JAR part against it without having the Lucene developer to install 
> JDK 19 in addition to Java 11/17. You can see the Panama code and also 
> the Gradle setup and classloading tricks at runtime (that 
> create/support the MR-JAR) here: 
> https://urldefense.com/v3/__https://github.com/apache/lucene/pull/912__;!!ACWV5N9M2RV99hQ!OEiAAKic8OeN0Sr4AsSAc5eshUkCuUj970Q9VyCwWGGUDCu1tGUp_mCuUZIHATdDbFTVAmpy_2bSjFrhN-l_q2zKI0iI$ 
>
> I also opened issues in Elasticsearch ad Opensearch, so users can test 
> it and report slowness/bugs earlier: 
> https://urldefense.com/v3/__https://github.com/elastic/elasticsearch/issues/90526__;!!ACWV5N9M2RV99hQ!OEiAAKic8OeN0Sr4AsSAc5eshUkCuUj970Q9VyCwWGGUDCu1tGUp_mCuUZIHATdDbFTVAmpy_2bSjFrhN-l_q4kTHR8k$ 
> , 
> https://urldefense.com/v3/__https://github.com/opensearch-project/OpenSearch/issues/4637__;!!ACWV5N9M2RV99hQ!OEiAAKic8OeN0Sr4AsSAc5eshUkCuUj970Q9VyCwWGGUDCu1tGUp_mCuUZIHATdDbFTVAmpy_2bSjFrhN-l_qx7bA-BE$ 
>
> Uwe
>