Not sure if this will make a difference but I would pull this line out of the for loop:
String[] s = table.getColumnHeaderCodes(); There is no point re-assigning this every loop iteration. If for some reason the array is actually being coppied, then that's expensive. -----Original Message----- From: Torbert Brian IT56 [mailto:[EMAIL PROTECTED]] Sent: Tuesday, June 25, 2002 9:46 AM To: 'POI Users List' Subject: RE: Anyone have performance problems? <CODESNIPIT> int nextCellNumber = 0; // Create first row and put some cells in it. Rows are 0 based. HSSFRow row = sheet.createRow((short)0); //Display the header columns for (int i=0; i<table.getColumnHeaderCodes().length; i++) { txc.getPerfTimer().startTiming("buildCell inner: "); String[] s = table.getColumnHeaderCodes(); HSSFCell cell = row.createCell((short)nextCellNumber++); //set style of cell cell.setCellStyle(headerStyle); // load cell cell.setCellValue(s[i]); txc.getPerfTimer().endTiming(); } </CODESNIPIT> I am using poi 1.5.0 and running the code on a Pentium 3 500mhz w512mb RAM. This is just a testing server our production server will be faster. In the code snipit above table is an object which holds a row of Header Columns and then rows of data. Here I have just included the print out of the header column. The rows are printed out similarly but with a different Cell Style. I have wrapped the code in the for loop with a timer and ran a test which included 3 ColumnHeaders. The results were: buildCell inner: : 71 milliseconds buildCell inner: : 90 milliseconds buildCell inner: : 110 milliseconds So to build the first Row in the workbook it took around 270 milliseconds. if you multiply that by 1000 rows your talking about 4.5 mins. Sure enough when I throw a count around the whole thing i was seeing about 4 mins. Can anyone see anything I am doing wrong that would cause this slow down? 90 milliseconds to build a cell seems high. Thanks Brian -----Original Message----- From: Andrew C. Oliver [mailto:[EMAIL PROTECTED]] Sent: Monday, June 24, 2002 6:17 PM To: 'POI Users List' Subject: RE: Anyone have performance problems? Look here for an idea of how fast I (a/o we) expect things to run: http://jakarta.apache.org/poi/tests/junit/ If there are special cases that are slower, I'd like to know. Please submit some unit tests. Perhaps we should start putting performance constraints on them. (an assert at the bottom that X seconds haven't passed perhaps based on some temporal adjustment by machine). The "reference" machine (in that its the one that generated the results) is a AMD Athlon T-Bird 900mhz w/512mb -- if you're running something slower/smaller of course things make take longer, but I think 3-4 minutes for 4000 cells is probably way out there. I'd like to see some code. -Andy On Mon, 2002-06-24 at 17:54, Hoffman, Jason wrote: > Yea, that does seem long. Our biggest problem has been OutOfMemory errors, > which were resolved by adding the java commmand line option to increase the > heap size. You might try that, yours may be slow because of memory > constraints? > > -----Original Message----- > From: Torbert Brian IT56 [mailto:[EMAIL PROTECTED]] > Sent: Monday, June 24, 2002 4:51 PM > To: 'POI Users List' > Subject: Anyone have performance problems? > > > Hi - > I was wondering what the typical time people experience when > creating a workbook of about 1000 rows and about 4 columns. This is taking > around 3-4 mins for us to generate. It seems a little long. Is this > normal? > > Thanks > > Brian > > -- > To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> > > -- > To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> > -- http://www.superlinksoftware.com - software solutions for business http://jakarta.apache.org/poi - Excel/Word/OLE 2 Compound Document in Java http://krysalis.sourceforge.net/centipede - the best build/project structure a guy/gal could have! - Make Ant simple on complex Projects! The avalanche has already started. It is too late for the pebbles to vote. -Ambassador Kosh -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
