Friends, Any thoughts regarding this? Any thoughts or suggestions would be greatly appreciated.
Thanks, Raghu ----- Original Message ----- From: [email protected] To: [email protected] Sent: Tuesday, June 8, 2010 4:07:45 PM GMT -05:00 US/Canada Eastern Subject: Re: Performance Issue with POI 3.6 as compared to 2.5.1 Nick, David, Thank you both for your response. I got held up with other work and hence couldn't respond earlier. Please clarify the following. >>My hunch is that you'll find HSSFWorkbook from 3.6 to be slightly faster than from 2.5, or otherwise little different.<< My understanding is that, to be able to generate .xlsx files I need to use XSSFWorkbook and NOT HSSFWorkbook. Hence that rules out the possibility of using HSSFWorkbook. Please correct me if I am wrong. Based on David's reply, here is what I tried. <This is the first time I am working with NIGHTLY builds. Please correct me if my approach is wrong> I downloaded the poi-3.7-SNAPSHOT-20100528.jar NIGHTLY build and replaced the earlier one: poi-3.6-20091214.jar So now I have 2 environments with the following settings to test the PERFORMANCE between POI 3.6 and 2.5.1. Env1: POI version 3.6 with XSSFWorkbook (updated with the above mentioned NIGHTLY build jar. Other 3.6 jars are the same) Env2: POI version 2.5.1 with HSSFWorkbook The report that I am generating has a SQL SELECT query which returns 65,000 records in 2 seconds. Env2 provides the file in less than 10 seconds. Env1 takes around 15 mins!! The BIG QUESTION for my project team is: Can POI EFFICIENTLY support generation of MS Excel 2007 (.xlsx) files which have more than 66,000 records? Now, I need to be able to make this decision to accordingly convey to the management. We had migrated from .CSV files to POI due to the user preference of native MS Excel files over CSV. If anybody has managed to achieve this, PLEASE HELP. Let me know if you need any further details. Regards, Raghu ----- Original Message ----- From: [email protected] To: [email protected] Sent: Tuesday, May 25, 2010 5:33:51 AM GMT -05:00 US/Canada Eastern Subject: Re: Performance Issue with POI 3.6 as compared to 2.5.1 On Mon, 24 May 2010, K raghavendra Rao wrote: > I was using POI 2.5.1 to generate .xls files until the record count > crossed the 65k+ limit set by Excel 2003. At this point, I switched to > POI 3.6 and to XSSFWorkbook (from the previous HSSFWorkbook) This'll be the main cause. My hunch is that you'll find HSSFWorkbook from 3.6 to be slightly faster than from 2.5, or otherwise little different. XSSFWorkbook is xml based (the whole of the ooxml file format is), and processing it needs a bit more memory and cpu than the older binary format. Otherwise, see David's reply about some recent xssf performance improvements Nick --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
