Optimising the performance
The default settings of the Delft-FEWS program are tuned for forecasting systems. These systems generally do not have a huge amount of data and table records. However, historical databases might have millions of table records, which may slow down the performance at the user interface and also the forecasting shell servers.
It is possible to change the default memory settings and to increase the performance. The settings below can be used for the OC, the FSS and stand alone systems.
Changes to *.jpif
The user interface is started by using a jpif file, that contains the JAVA settings. This file looks like:
..\jre -mx512m -cp $JARS_PATH$ nl.wldelft.fews.gui.explorer.Application WIS_Dommel_OC
The second line contains the definition for the maximum allocated memory, in this case 512 MB. This value can simply be changed to allow for more allocated memory.
To analyse the currently used amount of memory in the user interface, you can open the About box from the Help menu. There you see the next window:
In this case the allocated memory for the map is already huge. Therefore it might be useful to increase the allocated memory in the jpif.
Changes to global.properties
To increase the performance of handling time series (e.g. in graphs or spatial display) you can increase the default allocated memory for caching time series.
Therefor you should add the next line to the global.properties.
timeSeriesDefaultCacheSizeMB=100
In this example 100 MB is allocated. The default value is 10 MB.
You can also increase the allocated memory for time series that are created during task runs (at a forecasting shell). To do so you should add the next line to the global.properties.
timeSeriesTaskRunCacheSizeMB=100
In this example 100 MB is allocated. The default value is 30 MB.
Temporary time series (synchLevel 9) are written to the database when the size of the write cache is not large enough to hold them in memory. This will cause a lot of extra work for the rolling barrel later on. You can set the size of this cache in the global.properties.
timeSeriesWriteCacheSizeMB=100
In this example 100 MB is allocated. The default value is 10 MB.
Notice that these changes might require additional allocated memory in the jpif of mcproxy service that handles the FSS or in the jpif of the Stand Alone system.
