java - 在 MacOS 中运行 jmap 命令失败

Question

运行 jmap如下:

jmap -heap 5788

并得到失败的结果:

正在附加到进程 ID 5788，请稍候...
附加到进程时出错:

sun.jvm.hotspot.debugger.DebuggerException: Can't attach symbolicator to the process
sun.jvm.hotspot.debugger.DebuggerException: sun.jvm.hotspot.debugger.DebuggerException: Can't attach symbolicator to the process
    at sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal$BsdDebuggerLocalWorkerThread.execute(BsdDebuggerLocal.java:169)
    at sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal.attach(BsdDebuggerLocal.java:287)
    at sun.jvm.hotspot.HotSpotAgent.attachDebugger(HotSpotAgent.java:671)
    at sun.jvm.hotspot.HotSpotAgent.setupDebuggerDarwin(HotSpotAgent.java:659)
    at sun.jvm.hotspot.HotSpotAgent.setupDebugger(HotSpotAgent.java:341)
    at sun.jvm.hotspot.HotSpotAgent.go(HotSpotAgent.java:304)
    at sun.jvm.hotspot.HotSpotAgent.attach(HotSpotAgent.java:140)
    at sun.jvm.hotspot.tools.Tool.start(Tool.java:185)
    at sun.jvm.hotspot.tools.Tool.execute(Tool.java:118)
    at sun.jvm.hotspot.tools.JInfo.main(JInfo.java:138)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.tools.jinfo.JInfo.runTool(JInfo.java:108)
    at sun.tools.jinfo.JInfo.main(JInfo.java:76)
Caused by: sun.jvm.hotspot.debugger.DebuggerException: Can't attach symbolicator to the process
    at sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal.attach0(Native Method)
    at sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal.access$100(BsdDebuggerLocal.java:65)
    at sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal$1AttachTask.doit(BsdDebuggerLocal.java:278)
    at sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal$BsdDebuggerLocalWorkerThread.run(BsdDebuggerLocal.java:144)

Answer 1

问题在于符号化器尝试符号化 macOS 内核，但由于 macOS 上的权限而失败。
在较新的版本上，您可以使用 jshdb:

 jhsdb jmap --heap --pid <pid>

您还可以使用 jcmd <pid> GC.heap_info 获取信息.