Description Yuhan Zhang 2011-11-28 20:15:36 EST

Created attachment 207638 [details]
the error log file from the crashed process.

It happens in time that JRE crashes while a SwtBrowser is standing in a loop awaiting requests coming in through "Browser.setUrl(String)" and "Browser.evaluate(String)". This doesn't have happen with particular urls (when each problematic url is tested separately, they didn't appear), but it happens overtime when multiple requests on the same browser. It may also result in hanging as asyncExec not being responsive at executing the assigned Runnable.

(10 concurrent processes of the same app are loaded and executed in memory.)


The below is the taken-apart code to represent the situation:

- The SwtBrowser is initialized in one thread using:


Display display = new Display();
Shell shell = new Shell(display);
shell.setLayout(new FillLayout());
shell.open();
Browser browser = new Browser(shell, SWT.MOZILLA);
Rectangle bound = new Rectangle(0,0,width,height);
shell.setBounds(bound);
browser.setBounds(bound);
Thread uiThread = Thread.currentThread();

while ( !shell.isDisposed() && !Thread.currentThread().isInterrupted()) {
	if (!display.readAndDispatch())
		display.sleep();
}


- The request for setting urls are coming in through asynExec from a seperate thread:

final String url = "http://www.example.com";
display.asyncExec( new Runnable() {
	public void run() {
		browser.setUrl( "about:blank" );    // erase previous content
		browser.setUrl(url);       // may hang or crash overtime
	}
} );


- The requests for evaluating javascript are coming in through the 3rd thread after 10 seconds of time-out :

Thread deplayedProcessingThread = new Thread() {
	@Override
	public void run() {
		try {
			int maxWait = 10*1000;
			LOGGER.info("wait browser to load for " + maxWait + " ms");
			Thread.sleep(maxWait);
			LOGGER.info("Wake up from for waiting for " + url);
		} catch (InterruptedException e) {
			LOGGER.info("deplayedProcessingThread interrupted, and omitted");
			return;
		}
		
		delayedProcessingThread = null;
		LOGGER.info("processing from the timeout thread. url=" + url);
		display.asyncExec( new Runnable() {
			public void run() {
				browser.stop();
				Object returnValue = browser.evaluate( MY_JAVASCRIPT_WITH_OBJECTS_RETURNED ));
				... // processing with the returnValue
			}
		});
	}
};
deplayedProcessingThread.start();



#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0xb7e61b92, pid=18595, tid=2657889168
#
# JRE version: 6.0_22-b04
# Java VM: Java HotSpot(TM) Client VM (17.1-b03 mixed mode linux-x86 )
# Problematic frame:
# C  [libc.so.6+0x6fb92]
#
# An error report file with more information is saved as:
# /home/hadoop/hs_err_pid18595.log


Other fatal error may also occur (but only one log file has been attached):

Here are the error messages:
#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x9cca4519, pid=10793, tid=2657803152
#
# JRE version: 6.0_22-b04
# Java VM: Java HotSpot(TM) Client VM (17.1-b03 mixed mode linux-x86 )
# Problematic frame:
# C  [libmozjs.so.1d+0xd519]  JS_SaveFrameChain+0x13
#
# An error report file with more information is saved as:
# /home/hadoop/hs_err_pid10793.log
#
# If you would like to submit a bug report, please visit:
#   http://java.sun.com/webapps/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#



Another type of error message:
#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0xb7f3da00, pid=16152, tid=2657725328
#
# JRE version: 6.0_22-b04
# Java VM: Java HotSpot(TM) Client VM (17.1-b03 mixed mode linux-x86 )
# Problematic frame:
# C  [libpthread.so.0+0x7a00]  pthread_mutex_lock+0x20
#
# An error report file with more information is saved as:
# /home/hadoop/hs_err_pid16152.log
#
# If you would like to submit a bug report, please visit:
#   http://java.sun.com/webapps/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#