The only options that drastically affect HSSF's running out of memory is the -mx option. The "heap space". I don't think increasing stack space is very important (objects are stored on the heap and we don't make significant use of recursion). As for building on disk...we're planning that in a later release, but next release will mostly focus (as far as this area goes) on reducing memory consumption in the first place. I want to do it with as little effect on performance, swapping to disk will have a drastic effect on performance, but should be an option (later....4.0 probably).
-Andy [EMAIL PROTECTED] wrote: >Ok, I've done some extensive research on the command line options outlined >below. These appear to be non-standard options one of which (-oss?) I >couldn't even find any documentation on. Further more some appear to be >Solaris/Linux specific. The there doesn't appear to be a -server option for >the Windows version of the Java launcher. Would the Windows equivalent be >-classic? (I don't think so b/c -classic is a lower optimization option for >bypassing the Hotspot VM.) I ran command line help on the AS/400 via QSH >and Java -? and there doesn't appear to be a -classic or a -server option >available there. The AS/400 help also did not mention either the -oss or >the -ss options either. The one thing that does seem consistent across the >board is the -ms and -mx optins. I will try them along with some minor code >optimizations but I'm not sure how or if I can rely on them because I plan >ultimately to run this utlity on the AS/400 via JNI. I'm not sure how to >set these options via JNI. I'm wondering if there is a way to stream the >output to a file as I'm reading data from the database as opposed to >building the document entirely in memory then writing to disk. > >Thank you for all of your help, >Cliff > > > >"Jackson, Stephen" <[EMAIL PROTECTED]> >08/09/2002 05:00 PM > > > > > >Please respond to "POI Users List" <[EMAIL PROTECTED]> > >To: "'POI Users List'" <[EMAIL PROTECTED]> >cc: > >Subject: RE: Out of memory error... > > >Remember the default setting of the JVM >The JVM runs as a client unless you specify -server (which will process you >code about 50% faster >by default your JVM is only 64MB. > >The follow gives sets the initial heap to 975MB and the max size the same. >java -server -ms975m -mx975m -oss6400k -ss2048k > >You need to do some research and figure out the parameters that best fit >what you are doing. >You need to use Runtime to monitor you memory. >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] >Sent: Friday, August 09, 2002 5:01 PM >To: POI Users List >Subject: Out of memory error... > > > >Hello all, > >I recently created a conversion utility that reads processes records from a >result set into an HSSFWorksheet object. I just ran across a scenario where >I am getting an out of memory error. I was testing it against a moderately >sized file on an AS/400 system with the code running on my Dell 900Mhz 20G >PC Win2K PC. I have 128Meg RAM and it was running in the Forte Community >Edition IDE from Sun. I did have about 3-4 other windows open but I hardly >think that would have caused a difference. I'm wondering if there's >anything I can do to alleviate this. I'm thinking the out-of-memory is due >to too many object being created with the result set containing about 4600 >records each w/ about 25 or 30 fields. This combined with all of the HSSF >sheet, row, and font objects for formatting and writing the data was >probably too much. Is there any low memory alternative to what I'm trying? > >Regards, >Cliff > > > >-- >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]> > > > > -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
