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HP- > Thank you, Don, for this exhaustive information. I'm glad I contributed > to the users' guide ;-) A first cut at the user's guide page will be in tomorrow's build under the miscellaneous section (Performance Tuning). Comments are welcome. Don. > Unidata IDV Support wrote: > > HP- > > > >> Institution: EUMETSAT > >> Package Version: 2.1b1 > >> Operating System: os.name:Windows XP; os.arch:x86; os.version:5.1; > >> Hardware Information: java.vendor:Sun Microsystems Inc.; > >> java.version:1.5.0_06; java.home:C:\\Program Files\\IDV_2.1b1\\jre; > >> j3d.version:1.3.2 fcs (build12); j3d.vendor:Sun Microsystems, Inc.; > >> j3d.renderer:OpenGL; > >> Inquiry: Hi > >> > >> Every now and then IDV aborts when handling a couple of larger data sets. > >> I remeber having seen once something about heap size flashing at me before > >> abort. > >> I have been looking in the documentation for some hints about > >> "optimum" configration of memory use and the like, but was not very > >> successful. > >> Can you give any guidance in general and perhaps also for my is M$ XP T43b > >> ex-IBM notebook with 1MB of RAM. > > > > The best (only?) reference is in the FAQ: > > > > http://www.unidata.ucar.edu/software/idv/docs/userguide/Faq.html#faq1_cat3_12 > > > > 512m is probably best for a Windows system with 1 Gb of RAM. Windows > > takes up half of that anyway and once Windows has to start swapping, > > performance severely degrades. On a Linux system, you can probably > > get away with 700m for 1 Gb of memory as it does a much better > > job of swapping. All this also depends on what else you are running > > on the machine and how much memory it takes. On my XP system, sometimes > > Firefox ends up eating up > 120 Mb which affects my IDV. > > > > For a 2Gb system, you can probably allocate 1.5 Gb to the IDV. > > > > I think for the next release, it would be good to have a page on > > performance tuning. There are several other things you can do to > > reduce memory consumption: > > > > - turn off in memory caching - if you are only displaying/using an > > image once (i.e. not using it for multiple calcuations), you can > > keep from caching in memory. With caching on, we keep a copy of > > the image in memory for future access (true for grids as well). > > - set the max image size that will be displayed. This will allow > > you to download a large image, but it will be resampled before > > displaying if it is larger than the max pixel size you have asked > > for. > > (both of these options are under the Data and Formats tab of the > > Preferences dialog) > > > > - Turn on Fast Rendering. This will create displays without accounting > > for projection seams which uses more memory. If you are displaying > > the data in it's native projection, you can probably get away with > > this. If you run into problems (i.e. bad displays), let us know. > > Satellite projections are tricky and this may not always work. However, > > we can look into any problems you find. This option is available > > in the Preferences also. > > > > So now, I can just take this and put it in the user's guide. ;-) > > > > Don Murray > > > > > > > > Ticket Details > > =================== > > Ticket ID: STG-449976 > > Department: Support IDV > > Priority: Normal > > Status: Open > > > > > > > > Ticket Details =================== Ticket ID: STG-449976 Department: Support IDV Priority: Normal Status: Closed