Administering Charts

You can use ColdFusion Administrator to specify the number of charts to cache, the number of charting threads, and the disk file for caching images to disk. When a chart is created, ColdFusion caches it by using the Administrator cache settings. Therefore, when a repeated request is made for the same chart, ColdFusion looks in cache and loads it from there instead of rendering the chart again. You can make changes in the cache setting in ColdFusion Administrator. Figure 26.13 shows the ColdFusion page for changing the cache settings. You need to select the Charting option of the Server Settings menu on the left panel of the ColdFusion Administrator page.

Figure 26.13: The cache settings options of ColdFusion Administrator.

The various options on this page are

• Cache Type. This option allows you to set the type of cache: memory, or disk. Caching in memory is faster than disk caching.

• Maximum Number of Images in Cache. This option allows you to set the maximum number of charts to store in cache. The oldest charts are deleted to make room for new ones when the cache reaches its limit. The maximum number you can set here is 250.

• Maximum Number of Charting Threads. This option allows you to set the maximum number of chart requests that can be processed concurrently. You can use values 1 through 5 here.

• Disk Cache Location. This option allows you to specify the directory to store the charts when the cache type is disk.