Use ArrayList instead of LinkedList for known size #1643
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Spring JDBC unlike other modules uses LinkedList instead of ArrayList in several places. There is a large body of evidence suggesting that on contemporary hardware ArrayList is both faster and has less overhead than even in degenerate cases of empty lists [3] or unknown size. There are two places in Spring JDBC where the size of the list is known in advance and an ArrayList of the correct final size can be created [1] https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8011200 [2] http://cliffc.org/blog/2017/11/05/modern-hardware-performance-cache-lines/ [3] https://bugs.openjdk.java.net/browse/JDK-8011200 Issue: SPR-16378
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Spring JDBC unlike other modules uses LinkedList instead of ArrayList
in several places. There is a large body of evidence suggesting that on
contemporary hardware ArrayList is both faster and has less overhead
than even in degenerate cases of empty lists [3] or unknown size.
There are two places in Spring JDBC where the size of the list is known
in advance and an ArrayList of the correct final size can be created
[1] https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8011200
[2] http://cliffc.org/blog/2017/11/05/modern-hardware-performance-cache-lines/
[3] https://bugs.openjdk.java.net/browse/JDK-8011200
Issue: SPR-16378