Observability of the Java Virtual Machine

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The JVM is one of the most observable runtimes. It provides us lots of tools for troubleshooting a JVM application in production. 1. Thread observability Threads are how the JVM actually does work. When something is wrong in production, the symptom is almost always a thread: stopped, blocked, leaking etc. Thread dumps work on any JVM with no  instrumentation, no agents, no restarts. <Example project link with /threaddump endpoint>         // (1) Deadlock — two threads grab the same pair of locks in opposite order.         new Thread(() -> grab(LOCK_A, LOCK_B), "deadlock-A-then-B").start();         new Thread(() -> grab(LOCK_B, LOCK_A), "deadlock-B-then-A").start(); http://localhost:8080/actuator/threaddump To list the JVMS, we can use the command below. PS C:\observe-jvm> jps -lv 25296 jdk.jcmd/sun.tools.jps.Jps -Dapplication.home=C:\Program Files\Microsoft\jdk-21.0.3.9-hotspot -Xms8m -Djdk.module.main=...
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Spekülatif Thread kavramı ve Mitosis Derleyicisi

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Master dersi ödevi olarak bir sunum hazırladım ve konu olarak bir spekülatif thread alt yapısı sunan Mitosis derleyicisini ele aldım. Mitosis, ön hesaplama dilimlerine dayanan bir thread altyapısı sunuyor.
Çalışmada ele alınan bazı kavramlar şu şekilde:

  • Düzensiz (irregular) uygulamalar/programlar
  • Spekülatif paralleştirme
  • Thread'ler arası veri bağımlılıkları
  • Ön hesaplama dilimleri
  • Mitosis derleyici optimizasyonları
  • Doğuş ikilileri (spawning pairs)
  • Bellek bağımlılığı üzerinde spekülasyon

Sunum dosyası:

https://drive.google.com/file/d/0BzOiLjD_ovqLUTFCcEVrd1kyNFk/view?usp=sharing

Orjinal makale:

http://cseweb.ucsd.edu/~tullsen/pldi2005.pdf

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