This topic applies to db4o versions 6.2 and higher.
.NET:
configuration.Io(new RandomAccessFileAdapter())
Decreases memory consumption by using an IO adapter without caching.
Since db4o version 6.2 CachedIoAdapter is used by default. This IO adapter has some valuable advantages, however the disadvantage is increased memory consumption. Using RandomAccessFileAdapter can help to keep the memory consumption to the minimum.
An alternative way to control the memory consumption is to configure it in the CachedIoAdapter constructor:
.NET:
configuration.Io(new
CachedIoAdapter(delegateAdapter, page_size, page_count));
page_size * page_count - will define the maximum amount of memory used for caching.