Upps, I see your problem. I had the same situation. Your tiles have 3 bands, red,green and blue. So you need about 3 times more bytes compared to an image with a color table.
http://www.gdal.org/rgb2pct.html is the utility you need. Be careful, you cannot compare the file size of an image after applying the utility. The images are compressed, so you cannot simply divide file sizes by 3. Within the Java VM, the tiles have to be decompressed, merged and interpolated to get an image of the right size. You need much more memory and much more CPU power to process multiband images. IMPORTANT: You have to apply rgb2pct on the big picture, not on the tiles. Afterward you can use http://www.gdal.org/gdal_retile.html to create your tiles. Btw, you said you use Oracle. Do you have a license for Oracle Spatial ?. If this is the case, you can use this plugin http://docs.geoserver.org/stable/en/user/data/oraclegeoraster.html You only have to import the big picture,tiling and pyramids are created within Oracle. Hope this helps Christian Quoting DGIS Devels <[email protected]>: > Hi! We have tested with six layers: five Oracle DB layers and a ECW > mosaic. GeoWebCache stores tiles in the same machine where Geoserver > instances run. > > We generated "data" tiles in PNG (palette safe) and images in JPEG. I'm not > sure about the type of these images. I give you the result of the gdalinfo, > I hope it is useful: > > gdalinfo 2400_1338.jpeg > Driver: JPEG/JPEG JFIF > Size is 512, 512 > Coordinate System is `' > Corner Coordinates: > Upper Left ( 0.0, 0.0) > Lower Left ( 0.0, 512.0) > Upper Right ( 512.0, 0.0) > Lower Right ( 512.0, 512.0) > Center ( 256.0, 256.0) > Band 1 Block=512x1 Type=Byte, ColorInterp=Red > Band 2 Block=512x1 Type=Byte, ColorInterp=Green > Band 3 Block=512x1 Type=Byte, ColorInterp=Blue > > Thanks > > 2010/10/1 <[email protected]> > >> Some additional questions. >> >> You wrote about tiles, so you are talking about raster/image data ? >> >> Where are your tiles stored. On a shared drive or in a database ? >> >> if you use a database, which one ? >> >> Are your tiles multiband images or images with a color table. If you are >> unsure, send me the output of >> gdalinfo yourtile.png. I achieved a performance boost when switching from >> multiband images to images with a color table. >> >> Cheers >> Christian >> >> >> >> >> >> Quoting DGIS Devels <[email protected]>: >> >> Hi, we have a question about Geoserver performance. >>> >>> We have been trying for a couple of months to find a good configuration >>> that >>> offers a solution to our use case. You can see our current architecture in >>> the attachment: >>> - WebLogic cluster with 2 machines and 4 managed servers (2 per machine). >>> We >>> have tested it whit JRockit and Sun JVM. >>> - 4 Geoservers (one per managed server) >>> - 2 GeoWebCaches (one per machine) >>> - A software balancer which balances requests between GeoWebCaches and >>> Geoservers >>> >>> We've testing too with a lot of values c for parameters like memory, >>> render >>> memory, timeouts, DB connections ... >>> >>> Our goal is to support 85 concurrent users performing an average of 5 map >>> requests (near of 100 256x256 tiles) in a time of 10 minutes. It must be >>> equivalent, according to our calculations, to respond to some 85000 >>> requests >>> in those 10 minutes. >>> >>> So far, the max number of request we've been able to response is about >>> 30000 >>> tiles. In most cases, some GeoServers or GeoWebCaches instances crashes. >>> >>> Anybody has made similar tests? Do you think is possible to reach a >>> similar >>> performance? >>> >>> >> >> >> ---------------------------------------------------------------- >> This message was sent using IMP, the Internet Messaging Program. >> >> >> > ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program. ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ Geoserver-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-users
