我有一个Java进程存在奇怪的问题,会卡死(每天一两次),只有在我执行以下操作后才能恢复:
jstack -F ${PID}
当Java进程挂起时,如果我尝试使用jcmd进行线程转储,则会收到AttachNotSupportedException。我只能使用jstack -F进行线程转储,并且使用与启动Java进程的JRE版本同步的JDK版本。
我唯一能想到的是,也许操作系统调度程序不允许Java进程占用CPU时间,而如果我执行jstack -F,它会强制允许其运行?
欢迎任何反馈。
更新-1
今天再次发生这种情况。我首先检查了内存使用情况(99.1%)然后执行了jmap -heap,在堆转储后进程恢复正常。附上堆转储文件。
问候,
Cristi
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
启用 GC 日志后,当进程冻结时,以下是 GC 日志的末尾。
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