Hi all ! We do have a problem on using MapServer on raster datas.
Our datasets are made of multiple GeoTiff files. Each Tiff has his own overviews (2 4 8 16 32). We do not have an overview level. Our Tiff are projected in UTM xx depending on the location on earth. Our Tiff have coordinates in them, they are true GeoTiff files ; however they have tfw files for compatibility with third-party softwares. We have an high performance degradation when serving WMS clients as WorldWind and an home-made client ; more precisely, the degradation is happening on zoomed out requests. The cause seems to be the amount of data required to be loaded by mapserver for the rendering of one single request. Worldwind is requesting datas in latlong projection whereas our homemade client is requesting in UTM projection. Our server is an octo-core with 8Gb of RAM, we are using Win2003 Server and Mapserver comes from FWTools 1.3.2 (Mapserver 4.x then), it is hosted by an IIS 6.0 in CGI mode (not FastCGI). I set the GDAL_CACHEMAX to 200. I monitored the mapserv.exe behaviour in the task manager to see what was happening and I saw that mapserver was loading a huge amount of data (between 50Mb and 300Mb of data depending on the requests/datasets). I then monitored the mapserv.exe behaviour in the holy Procmon and there I saw some interesting things. First, the epsg file loaded by GDAL is loaded multiple times near the start of the process, I think it is loaded each time an epsg code is mentionned in the map file. As we are serving UTM, their epsg code (32631 for instance) are lying at the end of the file, so Mapserver was reading the file looking for those codes. I, then, moved those definitions to the beginning of the file, just after the latlong definition (epsg 4326). I launched the requests, and saw that the amount of datas being read was much lower, but the end-to-end was slow again. Then, I moved forward, in my procmon report and there I saw IT !! Mapserver is loading for each of our tiffs files, 6 other files !! Those files are : pcs.csv = 400 Kb, projop_wparm.csv = 165 Kb, gcs.csv = 35 Kb, unit_of_measure.csv = 20 Kb, datum.csv = 70 Kb, ellipsoid.csv = 10 Kb So, from what I see, for serving my request, mapserver is loading approximatively 700Kb of "external" datas and around 50/100 Kb of my 1Mb Tiff files. In order to serve a zoomed out request, I have 26 Tiff files. So, finally, mapserver is loading 20 Mo. So, here is my question : how could I make Mapserv to not load those files again and again... ??? Thanks in advance !! Benoît Andrieu PS : if anyone is interested, I can send my log files from Procmon to show which files are accessed. ================================================================================================================================================================================ My test requests : http://acquisitiontest/Cgi/bin/mapserv.exe?&request=GetMap&layers=Sonar_FRONT,Sonar_STARBOARD,Sonar_PORT&TRANSPARENT=TRUE&BGCOLOR=0xFFFFFF&map=C:\content\surveytemplate\LigneSudMoins600\MAP_62.map&srs=EPSG:32631&width=512&height=512&bbox=715102,4783144.81842247,716996,4783869.89482688&format=image/gif&version=1.1.1&styles= http://acquisitiontest/Cgi/bin/mapserv.exe?&request=GetMap&layers=Sonar_FRONT,Sonar_STARBOARD,Sonar_PORT&TRANSPARENT=TRUE&BGCOLOR=0xFFFFFF&map=C:\content\surveytemplate\LigneSudMoins600\MAP_62.map&srs=EPSG:4326&width=512&height=512&bbox=5.64654588699341,43.1704597473145,5.66959381103516,43.1764526367188&format=image/gif&version=1.1.1&styles= ================================================================================================================================================================================ My map file : #This Map Was Generated By Isdas do not modifie #Generaded : 10/15/2007 1:24:22 PM MAP Name"LigneSudMoins600" CONFIG "PROJ_LIB" "c:\Inetpub\wwwroot\Cgi\proj_lib\" EXTENT 5.64654588701225 43.1704597472872 5.66959381105485 43.17645263669 SIZE 512 512 IMAGETYPE PNG24 IMAGECOLOR 255 255 255 IMAGECOLOR 255 255 255 UNITS METERS OUTPUTFORMAT NAME PNG24 DRIVER "GD/PNG" MIMETYPE "image/png" EXTENSION PNG IMAGEMODE RGBA TRANSPARENT ON END PROJECTION "init=epsg:4326" END WEB IMAGEPATH "c:\ms_tmp\" IMAGEURL "http://ACQUISITIONTEST/ms_tmp"; METADATA "wms_title" "LigneSudMoins600" "wms_srs" "epsg:4326 epsg:32631" "wms_onlineresource" "http://ACQUISITIONTEST/WMS/Default.aspx?MapId=123"; END END LAYER NAME "Sonar" STATUS ON TILEINDEX "C:\content\surveytemplate\LigneSudMoins600\IDX_PIC_SS_65.shp" TILEITEM "location" TYPE RASTER UNITS METERS METADATA "wms_title" "Sonar" "wms_srs" "epsg:32631 epsg:27563 epsg:32631 epsg:32632 epsg:32633 epsg:32635" "wms_onlineresource" "http://ACQUISITIONTEST/WMS/Default.aspx?MapId=123"; END PROJECTION "init=epsg:32631" END OFFSITE 0 0 0 END LAYER NAME "Sonar_PORT" STATUS ON TILEINDEX "C:\content\surveytemplate\LigneSudMoins600\IDX_PIC_SS_65_PORT.shp" TILEITEM "location" TYPE RASTER UNITS METERS METADATA "wms_title" "Sonar_PORT" "wms_srs" "epsg:32631 epsg:27563 epsg:32631 epsg:32632 epsg:32633 epsg:32635" "wms_onlineresource" "http://ACQUISITIONTEST/WMS/Default.aspx?MapId=123"; END PROJECTION "init=epsg:32631" END OFFSITE 0 0 0 END LAYER NAME "Sonar_STARBOARD" STATUS ON TILEINDEX "C:\content\surveytemplate\LigneSudMoins600\IDX_PIC_SS_65_STARBOARD.shp" TILEITEM "location" TYPE RASTER UNITS METERS METADATA "wms_title" "Sonar_STARBOARD" "wms_srs" "epsg:32631 epsg:27563 epsg:32631 epsg:32632 epsg:32633 epsg:32635" "wms_onlineresource" "http://ACQUISITIONTEST/WMS/Default.aspx?MapId=123"; END PROJECTION "init=epsg:32631" END OFFSITE 0 0 0 END LAYER NAME "Sonar_FRONT" STATUS ON TILEINDEX "C:\content\surveytemplate\LigneSudMoins600\IDX_PIC_SS_65_FRONT.shp" TILEITEM "location" TYPE RASTER UNITS METERS METADATA "wms_title" "Sonar_FRONT" "wms_srs" "epsg:32631 epsg:27563 epsg:32631 epsg:32632 epsg:32633 epsg:32635" "wms_onlineresource" "http://ACQUISITIONTEST/WMS/Default.aspx?MapId=123"; END PROJECTION "init=epsg:32631" END OFFSITE 0 0 0 END #~~~ END
