无限 100% CPU 使用率在 java.io.FileInputStream.readBytes（本机方法）
2022-09-01 21:29:53
我现在正在调试一个程序，该程序每个外部进程有两个线程，这两个线程继续使用循环读取Process.getErrorStream（）和Process.getInputStream（）。while ((i = in.read(buf, 0, buf.length)) >= 0)
有时，当外部进程由于JVM崩溃而崩溃时（请参阅这些hs_err_pid.log文件），那些读取该外部进程的stdout / stderr的线程开始消耗100%的CPU并且永远不会退出。循环体未执行（我在那里添加了一个日志记录语句），因此无限循环似乎位于本机方法中。java.io.FileInputStream.readBytes
我已经在Windows 7 64位（jdk1.6.0_30 64位，jdk1.7.0_03 64位）和Linux 2.6.18（jdk1.6.0_21 32位）上复制了这一点。有问题的代码在这里，它是这样使用的。请参阅这些链接以获取完整代码 - 以下是有趣的部分：
private final byte[] buf = new byte[256];
private final InputStream in;
...
int i;
while ((i = this.in.read(this.buf, 0, this.buf.length)) >= 0) {
...
}
堆栈跟踪如下所示
"PIT Stream Monitor" daemon prio=6 tid=0x0000000008869800 nid=0x1f70 runnable [0x000000000d7ff000]
java.lang.Thread.State: RUNNABLE
at java.io.FileInputStream.readBytes(Native Method)
at java.io.FileInputStream.read(FileInputStream.java:220)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
at java.io.BufferedInputStream.read1(BufferedInputStream.java:258)
at java.io.BufferedInputStream.read(BufferedInputStream.java:317)
- locked <0x00000007c89d6d90> (a java.io.BufferedInputStream)
at org.pitest.util.StreamMonitor.readFromStream(StreamMonitor.java:38)
at org.pitest.util.StreamMonitor.process(StreamMonitor.java:32)
at org.pitest.util.AbstractMonitor.run(AbstractMonitor.java:19)
Locked ownable synchronizers:
- None
或
"PIT Stream Monitor" daemon prio=6 tid=0x0000000008873000 nid=0x1cb8 runnable [0x000000000e3ff000]
java.lang.Thread.State: RUNNABLE
at java.io.FileInputStream.readBytes(Native Method)
at java.io.FileInputStream.read(FileInputStream.java:220)
at org.pitest.util.StreamMonitor.readFromStream(StreamMonitor.java:38)
at org.pitest.util.StreamMonitor.process(StreamMonitor.java:32)
at org.pitest.util.AbstractMonitor.run(AbstractMonitor.java:19)
Locked ownable synchronizers:
- None
使用Sysinternals Process Explorer，我能够获得这些线程的本机堆栈跟踪。大多数情况下，超过 80% 的时间，堆栈跟踪如下所示：
ntdll.dll!NtReadFile+0xa
KERNELBASE.dll!ReadFile+0x7a
kernel32.dll!ReadFile+0x59
java.dll!handleRead+0x2c
java.dll!VerifyClassCodesForMajorVersion+0x1d1
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
这种情况也经常发生：
ntdll.dll!RtlNtStatusToDosErrorNoTeb+0x52
ntdll.dll!RtlNtStatusToDosError+0x23
KERNELBASE.dll!GetCurrentThreadId+0x2c
KERNELBASE.dll!CreatePipe+0x21a
kernel32.dll!ReadFile+0x59
java.dll!handleRead+0x2c
java.dll!VerifyClassCodesForMajorVersion+0x1d1
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
ntdll.dll!RtlNtStatusToDosErrorNoTeb+0x42
ntdll.dll!RtlNtStatusToDosError+0x23
KERNELBASE.dll!GetCurrentThreadId+0x2c
KERNELBASE.dll!CreatePipe+0x21a
kernel32.dll!ReadFile+0x59
java.dll!handleRead+0x2c
java.dll!VerifyClassCodesForMajorVersion+0x1d1
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
有时它执行这部分代码：
java.dll!VerifyClassCodesForMajorVersion+0xc3
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
java.dll!Java_sun_io_Win32ErrorMode_setErrorMode+0x847c
java.dll!VerifyClassCodesForMajorVersion+0xd7
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
jvm.dll!JNI_GetCreatedJavaVMs+0x1829f
java.dll!VerifyClassCodesForMajorVersion+0x128
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
jvm.dll+0x88c1
jvm.dll!JNI_GetCreatedJavaVMs+0x182a7
java.dll!VerifyClassCodesForMajorVersion+0x128
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
java.dll!VerifyClassCodesForMajorVersion+0x10b
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
jvm.dll!JNI_CreateJavaVM+0x1423
java.dll!VerifyClassCodesForMajorVersion+0x190
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
jvm.dll+0x88bf
jvm.dll!JNI_CreateJavaVM+0x147d
java.dll!VerifyClassCodesForMajorVersion+0x190
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
java.dll!VerifyClassCodesForMajorVersion+0x1aa
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
java.dll!VerifyClassCodesForMajorVersion+0x1c3
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
java.dll!VerifyClassCodesForMajorVersion+0x224
java.dll!Java_java_io_FileInputStream_readBytes+0x1d
有什么想法如何解决这个问题？这是 JVM 的已知问题吗？是否有解决方法？
