ch.qos.logback.core.issue.lbcore258

Class FileLockSimulator

java.lang.Object

ch.qos.logback.core.issue.lbcore258.FileLockSimulator

public class FileLockSimulator
extends Object

FileLockSimulator is a small application intended to simulate FileAppender in prudent mode. In this mode, the application obtains an exclusive lock on the file, writes to the file and then releases the lock.

  Usage:
   java  FileLockSimulator instanceName pathToLogFile delay
 where
 "instanceName" is the name given to the current instance of the application
 "pathToLogFile" is the path to the log file
 "delay" is the number of milliseconds of sleep observed every 128 writes
 

This small application requires only the JDK to compile and to execute.

FileLockSimulator should be launched as many times and from as many hosts as there will be JVMs writing to a log file in prudent mode. Performance should be quite good if "pathToLogFile" is on a local file system. On networked file systems such as NFS, performance depends on the speed of the network and NFS implementation. It has been observed that file locking over NFS is biased so that the current owner of the lock is favored over other processes. Thus, while one process hogs the lock for the log file, other processes starve waiting for the lock to the point of appearing deadlocked.

Constructor Summary

Constructors

Constructor and Description
FileLockSimulator()

Method Summary

Methods

Modifier and Type	Method and Description
static void	main(String[] args)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FileLockSimulator

public FileLockSimulator()

Method Detail

main

public static void main(String[] args)
                 throws IOException,
                        InterruptedException

Throws:

IOException

InterruptedException