How long are cached images saved for?

[imoehld]

I have reports that contain a logo image (loaded in from the database, converted to a BufferedImage, and passed in as a parameter), and I have set isUsingCache = true for these image elements. This setting works as expected, and significantly reduces the size of the exported pdf's (We have reports that can be hundreds of pages long, so this size reduction is necessary).

 

However, we have a logo image for each organization, and all of the reports for these organizations are generated on the same server. We are concerned that caching these logos could cause the cache to fill and eventually error out.

 

So, my question is relatively simple, how long will these cached images stay on the cache? Are they only cached for the duration of the creation of the report, or do we have to clear the image from the cache?