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容器篇中对于HashMap遍历方式的说明存在部分错误 #1411
Description
此处引用公众号文章中, 对于parallelStream遍历方式的性能分析有误
先说结论, 存在阻塞时parallelStream性能最高, 非阻塞时parallelStream性能最低
当遍历不存在阻塞时, parallelStream的性能是最低的:
Benchmark Mode Cnt Score Error Units
Test.entrySet avgt 5 288.651 ± 10.536 ns/op
Test.keySet avgt 5 584.594 ± 21.431 ns/op
Test.lambda avgt 5 221.791 ± 10.198 ns/op
Test.parallelStream avgt 5 6919.163 ± 1116.139 ns/op
加入阻塞代码Thread.sleep(10)后, parallelStream的性能才是最高的:
Benchmark Mode Cnt Score Error Units
Test.entrySet avgt 5 1554828440.000 ± 23657748.653 ns/op
Test.keySet avgt 5 1550612500.000 ± 6474562.858 ns/op
Test.lambda avgt 5 1551065180.000 ± 19164407.426 ns/op
Test.parallelStream avgt 5 186345456.667 ± 3210435.590 ns/op
Activity
Ahaola commentedon Apr 30, 2023
good