How to avoid a ColdFusion server hang

1. Create a file. eg. C:/temp/test.csv
2. populate this file with say million lines of sample data. eg. test
3. run the above script
4. you will notice coldfusion eating up the entire JVM memory

This is a potential pitfall, which will cause JRun to not release memory and lead to using up all memeory till the server becomes unresponsive.

Why does this happen?
Coldfusion is build as a layer on top of Java, coldfusion assumes the process to be a single request and does not release the old query objects.

A sample code to create a ColdFusion server Hang
<cfscript>
	fileReader = createObject("java", "java.io.FileReader").init("c:/temp/test.csv");
	bufferedReader = createObject("java", "java.io.BufferedReader").init(fileReader);

	try 
	{	curLine = '';
		
		do 
		{	curLine = bufferedReader.readLine();
			curLineCheck = IsDefined("curLine");
			
			if (curLineCheck) {
				insertData(curLine);
			}
		} while(curLineCheck);	
	} catch (Exception e) {
		// this indicates end of file, ok to ignore error 
	} 
	
	bufferedReader.close();
	fileReader.close();
</cfscript> 

<cffunction name="insertData" returntype="void">
	<cfargument name="line" type="String" required="true">
	
	<cfquery name="test" datasource="dsnCF">
		insert into someTable (col) values ('#line#')
	</cfquery>
</cffunction>



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