When using ArcSDE, you can set whether or not to preload all data in a raster catalog, set the method for counting features, pool Spatial Server instances connected to ArcSDE, and set a connection check interval.

Load method for raster catalogs

By default, all data in a raster catalog is validated and basic information about each row of raster is preloaded when a service is started. If you have a very large raster catalog with thousands of rows, it may not be practical to preload the entire catalog. In this situation, you can change a setting so the raster catalog is not loaded into memory, and raster rows are loaded on demand when the service is viewed. This method should only be employed if you set scale dependent visibility for layers referencing large raster catalogs. If the raster catalog layer is viewed at full extent, performance will be slow, and the request may time out.

Count mode

Two modes are available when counting ArcSDE features. When client mode is used, all features are counted by the ArcIMS Spatial Server, which in this case is a client to ArcSDE. When server mode is used, all features are counted using a log file in ArcSDE. The default is client mode and is the recommended configuration. In some cases, when very large datasets are in use, server mode counting may be faster. You must use this mode with caution. When server counting is used, the feature limits you set in your map configuration file or in Spatial Server configuration files are ignored and no limit can be placed on the number of features a user can request. When using shapefiles, counting is always client mode.

Connection sharing

You can pool Spatial Server instances connected to ArcSDE. This feature was added originally when licensing of ArcSDE limited the number of connections available for ArcIMS. Since there is no longer a limit on ArcSDE connections available to ArcIMS, it is recommended not to change the defaults.

When you start an ArcIMS Service accessing data in ArcSDE, one or more connections per Spatial Server instance is made to ArcSDE. By default, all server functions, such as Image Server or Query Server, have one connection to ArcSDE per Spatial Server instance. The exception is Geocode Server, which has three connections. These connections are persistent and remain whether ArcIMS services are stopped or running. Exercise caution when using connection sharing since changing the defaults may adversely affect performance.

Connection check interval

The connectioncheckinterval defines the time interval between attempts to reconnect to ArcSDE when an ArcSDE server is unavailable. For more information, see Setting timeouts.

Setting the preload option for raster catalogs

Changing the count mode for ArcSDE features

Changing the number of instances