Crystal Report Memory problem

how to ensure proper cleanup of reports

 

It is particularly important if your application comes under load.Reports left open take up resources, which, if left unchecked, can starve your app of resources, leading to performance degradation, report request denial, and out of memory problems.And one more thing is it will block the database resources also.

Destroy every  ReportSource

Every time a ReportClientDocument opens a report rpt file,the reference count for that report instance is incremented.  Every time an unique ReportSource is retrieved from the ReportClientDocument, the count is incremented.Every time a ReportClientDocument is closed, the reference count is decremented.  Every time a ReportSource is destroyed, the count is decremented.If ReportClientDocument or ReportSource is not cleaned up, then the instance will remain live and taking up resources until timeout garbage collects the object.

One important consideration is the following: even if you invoke ReportClientDocument.close(), that report may still not be closed. 

Here's a simple test: 
 (1) open a report with a ReportClientDocument.
(2) retrieve a ReportSource using the method ReportClientDocument.getReportSource().
(3) invoke the ReportClientDocument.close() method for that instance.
 (4) test the value of ReportClientDocument.isOpen() - you'll see that it's true!.
(5) pass the ReportSource object to the CrystalReportViewer, and invoke CrystalReportViewer.dispose().
(6) now check ReportClientDocument.isOpen() again - you'll see that it's false, i.e., that the instance  has been cleaned up.
Another consideration:   the only way to dispose the ReportSource is to pass it to a viewer object 

Invoking viewer dispose() will in turn invoke the proper dispose method for the ReportSource.

 

we will prove this in one more way

before opening of report in application open the sql editor and run the below query  

 

SHOW FULL PROCESSLIST

 

IT DISPLAYS NO OF PROCESS ID'S  

 

after that open the report and again run the above query one more process id created even after closing of the report process id not decreasing 

that is why with crystal reports code we are facing some memory problems. So better to use crviewer.dispose() .

        

Browser event firing when closing the browser ?.

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