Hi In my client/server web application, i want to generate pdf reports for clients. I have a 20 thousand recorded dataset (approximately 10 thousand pdf pages) I tried JRFileVirtualizer but it didn't work for this huge set. Indeed, it worked fine for nearly 2500 recorded sets. And then i used JRSwapFileVirtualizer but it did not work too. My report consists of 2 subreports and a two times repeating image per a page. After my attempts i got some error messages like these: FATAL ERROR in native method: JDWP NewGlobalRef, jvmtiError=JVMTI_ERROR_NULL_POINTER(100) JDWP exit error JVMTI_ERROR_NULL_POINTER(100): NewGlobalRef or No input source supplied to the exporter. Here is some of my code snippet: Code:JRSwapFile mySwap = new JRSwapFile(TEMP_FILE_PATH,100,100); JRSwapFileVirtualizer swapVirtualizer = new JRSwapFileVirtualizer(JRFILEVIRTUALIZER_OBJECT_COUNT_INVOICE,mySwap); swapVirtualizer.setReadOnly(true); Map parameters = new HashMap(); parameters.put("INVOICE_SUBREPORT_1", subreport1); parameters.put("INVOICE_SUBREPORT_2", subreport2); parameters.put(JRParameter.REPORT_VIRTUALIZER, swapVirtualizer); jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, obj); Any help would be appreciated. Thanks in advance. -ahmet.