010 Editor features a powerful data engine that enables loading huge files and cutting and pasting large blocks of memory very quickly (see Introduction to the Data Engine for more information). The Cache Options dialog controls various options of the data engine. Open the Cache Options dialog by clicking the 'Tools > Options...' menu option and selecting 'Cache' from the list.
When accessing files, data that is loaded into memory is stored in a cache. The size of the cache can be specified using the Memory Limit options. Select the MB toggle and enter the cache limit in number of megabytes. Alternately, select the % of Physical Memory toggle and enter the percentage of physical memory that should be used for the cache (between 1 and 100). Note that physical memory does not include any system virtual memory (using the Windows swap file). Once too much data is loaded into the cache, data will be written to a swap file on disk and see the Directory Options dialog to control where the swap file is written.
Clicking Reset will return all cache options to their default values.