On Tue, 16 Nov 2021 09:45:56 GMT, Сергей Цыпанов <d...@openjdk.java.net> wrote:
>> Please review this PR which aims to optimize the implementation of the >> `toString` method we provide for records. A benchmark comparing the >> implementation we are providing for records with lombok found out that >> lombok is much faster mainly because our implementation uses >> `String::format`. This fix is basically delegating on >> StringConcatFactory::makeConcatWithConstants which is faster. >> >> TIA >> >> This is the result of the benchmark comparing records to lombok with vanilla >> JDK: >> >> Benchmark Mode Cnt Score Error Units >> MyBenchmark.base avgt 4 0.849 ± 0.111 ns/op >> MyBenchmark.equals_record avgt 4 7.343 ± 2.740 ns/op >> MyBenchmark.equals_value avgt 4 6.644 ± 1.920 ns/op >> MyBenchmark.record_hash_code avgt 4 5.763 ± 3.882 ns/op >> MyBenchmark.record_to_string avgt 4 262.626 ± 12.574 ns/op >> <------ Before >> MyBenchmark.value_class_to_string avgt 4 30.325 ± 21.389 ns/op >> MyBenchmark.value_hash_code avgt 4 5.048 ± 3.936 ns/op >> >> >> after this patch: >> >> Benchmark Mode Cnt Score Error Units >> MyBenchmark.base avgt 4 0.680 ± 0.185 ns/op >> MyBenchmark.equals_record avgt 4 5.599 ± 1.348 ns/op >> MyBenchmark.equals_value avgt 4 5.718 ± 4.633 ns/op >> MyBenchmark.record_hash_code avgt 4 4.628 ± 4.368 ns/op >> MyBenchmark.record_to_string avgt 4 26.791 ± 1.817 ns/op >> <------- After >> MyBenchmark.value_class_to_string avgt 4 35.473 ± 2.626 ns/op >> MyBenchmark.value_hash_code avgt 4 6.152 ± 5.101 ns/op > > src/java.base/share/classes/java/lang/runtime/ObjectMethods.java line 264: > >> 262: .map(g -> g.type().returnType()) >> 263: .toList() >> 264: .toArray(new Class<?>[getters.length]); > > Why not `new Class[0]`? It's likely to be faster, isn't it? (I'm not reviewer.) I think `.toArray(Class<?>[]::new)` should be better here. `.toList` seems unnecessary. ------------- PR: https://git.openjdk.java.net/jdk/pull/6403
