//重新分配内存 public native long reallocateMemory(long address, long bytes); //分配内存 public native long allocateMemory(long bytes); //释放内存 public native void freeMemory(long address); //在给定的内存块中设置值 public native void setMemory(Object o, long offset, long bytes, byte value); //从一个内存块拷贝到另一个内存块 public native void copyMemory(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes); //获取值,不管java的访问限制,其他有类似的getInt,getDouble,getLong,getChar等等 public native Object getObject(Object o, long offset); //设置值,不管java的访问限制,其他有类似的putInt,putDouble,putLong,putChar等等 public native void putObject(Object o, long offset); //从一个给定的内存地址获取本地指针,如果不是allocateMemory方法的,结果将不确定 public native long getAddress(long address); //存储一个本地指针到一个给定的内存地址,如果地址不是allocateMemory方法的,结果将不确定 public native void putAddress(long address, long x); //该方法返回给定field的内存地址偏移量,这个值对于给定的filed是唯一的且是固定不变的 public native long staticFieldOffset(Field f); //报告一个给定的字段的位置,不管这个字段是private,public还是保护类型,和staticFieldBase结合使用 public native long objectFieldOffset(Field f); //获取一个给定字段的位置 public native Object staticFieldBase(Field f); //确保给定class被初始化,这往往需要结合基类的静态域(field) public native void ensureClassInitialized(Class c); //可以获取数组第一个元素的偏移地址 public native int arrayBaseOffset(Class arrayClass); //可以获取数组的转换因子,也就是数组中元素的增量地址。将arrayBaseOffset与arrayIndexScale配合使用, 可以定位数组中每个元素在内存中的位置 public native int arrayIndexScale(Class arrayClass); //获取本机内存的页数,这个值永远都是2的幂次方 public native int pageSize(); //告诉虚拟机定义了一个没有安全检查的类,默认情况下这个类加载器和保护域来着调用者类 public native Class defineClass(String name, byte[] b, int off, int len, ClassLoader loader, ProtectionDomain protectionDomain); //定义一个类,但是不让它知道类加载器和系统字典 public native Class defineAnonymousClass(Class hostClass, byte[] data, Object[] cpPatches); //锁定对象,必须是没有被锁的 public native void monitorEnter(Object o); //解锁对象 public native void monitorExit(Object o); //试图锁定对象,返回true或false是否锁定成功,如果锁定,必须用monitorExit解锁 public native boolean tryMonitorEnter(Object o); //引发异常,没有通知 public native void throwException(Throwable ee); //CAS,如果对象偏移量上的值=期待值,更新为x,返回true.否则false.类似的有compareAndSwapInt,compareAndSwapLong,compareAndSwapBoolean,compareAndSwapChar等等。 public final native boolean compareAndSwapObject(Object o, long offset, Object expected, Object x); // 该方法获取对象中offset偏移地址对应的整型field的值,支持volatile load语义。类似的方法有getIntVolatile,getBooleanVolatile等等 public native Object getObjectVolatile(Object o, long offset); //线程调用该方法,线程将一直阻塞直到超时,或者是中断条件出现。 public native void park(boolean isAbsolute, long time); //终止挂起的线程,恢复正常.java.util.concurrent包中挂起操作都是在LockSupport类实现的,也正是使用这两个方法 public native void unpark(Object thread); //获取系统在不同时间系统的负载情况 public native int getLoadAverage(double[] loadavg, int nelems); //创建一个类的实例,不需要调用它的构造函数、初使化代码、各种JVM安全检查以及其它的一些底层的东西。即使构造函数是私有,我们也可以通过这个方法创建它的实例,对于单例模式,简直是噩梦。 public native Object allocateInstance(Class cls) throws InstantiationException;
"taskExecutor-5" #638 prio=5 os_prio=0 tid=0x00007f970800b000 nid=0x1be3 waiting on condition [0x00007f9632008000] java.lang.Thread.State: WAITING (parking) at sun.misc.Unsafe.park(Native Method) - parking to wait for <0x00000000e134e670> (a java.util.concurrent.CompletableFuture$Signaller) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) at java.util.concurrent.CompletableFuture$Signaller.block(CompletableFuture.java:1693) at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3323) at java.util.concurrent.CompletableFuture.waitingGet(CompletableFuture.java:1729) at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1895) at com.appleframework.file.provider.fdfs.FdfsProvider.upload(FdfsProvider.java:61) at com.appleframework.file.spring.AbstractFSProviderSpringFacade.upload(AbstractFSProviderSpringFacade.java:70) at com.chedaia.biz.renew.provider.service.impl.CustomerShoppingServiceImpl$1.run(CustomerShoppingServiceImpl.java:956) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748)
3282788 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410) 3282789 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410) 3282790 Exception in thread "pool-250-thread-43" java.lang.StackOverflowError 3282791 at java.util.AbstractCollection.toArray(AbstractCollection.java:183) 3282792 at java.lang.String.split(String.java:2378) 3282793 at com.chedaia.task.address.util.ParkingPointUtil.isGps(ParkingPointUtil.java:32) 3282794 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:406) 3282795 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410) 3282796 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410) 3282797 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410) 3282798 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410) 3282799 at com.chedaia.task.address.util.ParkingPointUtil.getPreviewGpsPoint(ParkingPointUtil.java:410)
原因
递归调用次数太多导致 且启动脚本中设置了-Xss
1
-XX:PermSize=128m -Xss256k
解决办法
由于涉及到的代码依赖较多,先不改动代码 加大线程栈大小到2m
1
-XX:PermSize=128m -Xss2m
线程栈大小与递归次数测试
代码
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public static void main(String[] args) { recursion(0); }
public static void recursion(int i) { System.out.println(i); i++; recursion(i); }
执行结果
结果:966
此时的栈设置为: -Xss128k
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963 964 965 966 Exception in thread "main" java.lang.StackOverflowError at sun.nio.cs.UTF_8.updatePositions(UTF_8.java:77) at sun.nio.cs.UTF_8.access$200(UTF_8.java:57) at sun.nio.cs.UTF_8$Encoder.encodeArrayLoop(UTF_8.java:636) at sun.nio.cs.UTF_8$Encoder.encodeLoop(UTF_8.java:691) at java.nio.charset.CharsetEncoder.encode(CharsetEncoder.java
public static void recursion(int i) { System.out.println(i); long a = 1l; long b = 2l; long c = a + b; i++; recursion(i); }
在栈大小设置为: -Xss128k 时,结果是:623
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620 621 622 623 java.lang.StackOverflowError at sun.nio.cs.UTF_8.updatePositions(UTF_8.java:77) at sun.nio.cs.UTF_8.access$200(UTF_8.java:57) at sun.nio.cs.UTF_8$Encoder.encodeArrayLoop(UTF_8.java:636) at sun.nio.cs.UTF_8$Encoder.encodeLoop(UTF_8.java:691)
[mysqld] # set basedir to your installation path basedir=D:/mysql/mysql-5.7.23-winx64 # set datadir to the location of your data directory datadir=D:/mysql/mysql-5.7.23-winx64/data
[mysqld] # 指定端口 port=3307 # set basedir to your installation path basedir=D:/mysql/mysql-5.7.23-winx64-3307 # set datadir to the location of your data directory datadir=D:/mysql/mysql-5.7.23-winx64-3307/data
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | sys | | test | | wwh | +--------------------+ 6 rows in set (0.00 sec)
mysql> status; -------------- mysql Ver 14.14 Distrib 5.7.23, for Win64 (x86_64)
Connection id: 2 Current database: Current user: root@localhost SSL: Not in use Using delimiter: ; Server version: 5.7.23 MySQL Community Server (GPL) Protocol version: 10 Connection: localhost via TCP/IP Server characterset: latin1 Db characterset: latin1 Client characterset: gbk Conn. characterset: gbk TCP port: 3307 Uptime: 7 min 37 sec
show binlog events\G
show master status\G
查询命令
在master上查看当前有多少个从节点
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select * from information_schema.processlist as p where p.command = 'Binlog Dump';