alstjrdl9511790

덧붙이자면, -Djdk.tracePinnedThreads와 open jdk 23 이하에서 제공하는 JFR 이벤트는 성격이 다릅니다. -Djdk.tracePinnedThreads는 pinning이 일어나자 마자 stack trace가 찍힙니다. 하지만 jdk 21 이하에서 제공하는 JFR 이벤트는 후행 이벤트[1]입니다. pinning이 일어난 로직이 끝나야 이벤트가 출력됩니다. open jdk 24 이상부터는 -Djdk.tracePinnedThreads를 JFR로 완전히 대체할 수 있다고 해야 더 명확할 것 같습니다[2]. 물론 작성자님이 올리신 것 처럼 -Djdk.tracePinnedThreads를 권장하진 않습니다[3]. 다만 이를 대체할 기능이 크게 없네요😅&nbsp;[1]<blockquote><code>jdk.VirtualThreadPinned</code> indicates that a virtual thread was parked while pinned, i.e., without releasing its platform thread (see <a target="_blank" rel="noopener noreferrer nofollow" href="https://openjdk.org/jeps/444#Pinning">above</a>). This event is enabled by default, with a threshold of 20ms. <a target="_blank" rel="noopener noreferrer nofollow" href="https://openjdk.org/jeps/444">https://openjdk.org/jeps/444</a></blockquote>[2]<blockquote>A <code>jdk.VirtualThreadPinned</code> event is recorded by JDK Flight Recorder (JFR) whenever a virtual thread blocks inside a <code>synchronized</code> method. This event has been useful to identify code that would benefit from being changed to make less use of <code>synchronized</code> methods and statements, to not block while inside such constructs, or to replace such constructs with <code>java.util.concurrent</code> locks. <a target="_blank" rel="noopener noreferrer nofollow" href="https://openjdk.org/jeps/491">https://openjdk.org/jeps/491</a></blockquote>[3]<blockquote>As regards jdk.tracePinnedThreads. We want this system property to go away, it's just unfortunate that it seems to be widely used.<a target="_blank" rel="noopener noreferrer nofollow" href="https://github.com/openjdk/jdk/pull/17221#issuecomment-1874211812">https://github.com/openjdk/jdk/pull/17221#issuecomment-1874211812</a></blockquote>

pinned 확인법

이해했습니다 ㅎㅎ 인덱스를 하루 단위로 생성한다고 생각을 못했네요! 감사합니다!

6강 10분 색인 과정에 대해 질문 있습니다.

감사합니다 덕분에 쉽게 했네요 ㅎㅎ

alstjrdl9511790

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