Java 進程在我使用 jstack -F 進行線程轉儲后不會重新啟動而是恢復

Question

我的 Java 進程有一個奇怪的問題，該進程卡住了（每天一次/兩次），它只有在我執行后才能恢復：

jstack -F ${PID}

當 Java 進程卡住時，如果我嘗試使用 jcmd 進行線程轉儲，我會收到 AttachNotSupportedException。

我只設法使用 jstack -F 進行線程轉儲，並使用與 JRE 版本同步的 JDK 版本，用於啟動 java 進程的 JRE 版本。

我唯一能想到的是，也許操作系統調度程序不允許 Java 進程的 CPU 時間，如果我執行 jstack -FI 強制它允許它運行？

任何反饋將不勝感激。

問候，

克里斯蒂

更新-1

今天又發生了。 我檢查的第一件事是那個盒子上使用的 memory (99.1%)。 之后我執行了一個 jmap -heap，並且在堆轉儲后進程恢復沒有任何問題。 附加堆轉儲。

jmap -heap 7703
Attaching to process ID 7703, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.162-b12

using thread-local object allocation.
Parallel GC with 2 thread(s)

Heap Configuration:
   MinHeapFreeRatio         = 0
   MaxHeapFreeRatio         = 100
   MaxHeapSize              = 536870912 (512.0MB)
   NewSize                  = 89128960 (85.0MB)
   MaxNewSize               = 178782208 (170.5MB)
   OldSize                  = 179306496 (171.0MB)
   NewRatio                 = 2
   SurvivorRatio            = 8
   MetaspaceSize            = 21807104 (20.796875MB)
   CompressedClassSpaceSize = 1073741824 (1024.0MB)
   MaxMetaspaceSize         = 17592186044415 MB
   G1HeapRegionSize         = 0 (0.0MB)

Heap Usage:
PS Young Generation
Eden Space:
   capacity = 143130624 (136.5MB)
   used     = 73244792 (69.85167694091797MB)
   free     = 69885832 (66.64832305908203MB)
   51.1733897003062% used
From Space:
   capacity = 17825792 (17.0MB)
   used     = 8176960 (7.79815673828125MB)
   free     = 9648832 (9.20184326171875MB)
   45.871510225183826% used
To Space:
   capacity = 17825792 (17.0MB)
   used     = 0 (0.0MB)
   free     = 17825792 (17.0MB)
   0.0% used
PS Old Generation
   capacity = 243269632 (232.0MB)
   used     = 23534032 (22.443801879882812MB)
   free     = 219735600 (209.5561981201172MB)
   9.674052534432247% used

25964 interned Strings occupying 2759784 bytes.

更新-2

啟用 GC 日志后，當進程凍結時，這是 GC 日志的尾部。

2020-09-02T06:51:11.286+0000: 86020.549: Total time for which application 

threads were stopped: 0.0001978 seconds, Stopping threads took: 0.0000666 seconds
2020-09-02T06:51:11.286+0000: 86020.550: Application time: 0.0000610 seconds
2020-09-02T06:51:11.286+0000: 86020.550: Total time for which application threads were stopped: 0.0001793 seconds, Stopping threads took: 0.0000589 seconds
2020-09-02T06:51:11.287+0000: 86020.550: Application time: 0.0003371 seconds
2020-09-02T06:51:11.287+0000: 86020.550: Total time for which application threads were stopped: 0.0001749 seconds, Stopping threads took: 0.0000283 seconds
2020-09-02T06:51:11.287+0000: 86020.550: Application time: 0.0001277 seconds
2020-09-02T06:51:11.287+0000: 86020.550: Total time for which application threads were stopped: 0.0001554 seconds, Stopping threads took: 0.0000364 seconds
2020-09-02T06:51:11.287+0000: 86020.551: Application time: 0.0000400 seconds
2020-09-02T06:51:11.287+0000: 86020.551: Total time for which application threads were stopped: 0.0001082 seconds, Stopping threads took: 0.0000158 seconds
2020-09-02T06:51:11.288+0000: 86020.552: Application time: 0.0010649 seconds
2020-09-02T06:51:11.288+0000: 86020.552: Total time for which application threads were stopped: 0.0001945 seconds, Stopping threads took: 0.0000571 seconds
2020-09-02T06:51:11.289+0000: 86020.552: Application time: 0.0001078 seconds
2020-09-02T06:51:11.289+0000: 86020.552: Total time for which application threads were stopped: 0.0001852 seconds, Stopping threads took: 0.0000336 seconds
2020-09-02T06:51:11.289+0000: 86020.552: Application time: 0.0000366 seconds
2020-09-02T06:51:11.289+0000: 86020.552: Total time for which application threads were stopped: 0.0000910 seconds, Stopping threads took: 0.0000180 seconds
2020-09-02T06:51:11.289+0000: 86020.552: Application time: 0.0000412 seconds
2020-09-02T06:51:11.289+0000: 86020.553: Total time for which application threads were

Answer 1

如果在使用 jcmd 獲取線程轉儲時收到 AttachNotSupportedException，請嘗試在與 java 進程運行相同的用戶下運行 jcmd。 請參閱com.sun.tools.attach.AttachNotSupportedException：無法打開套接字文件：目標進程沒有響應或 HotSpot VM 未加載