If the MDS runs out of memory, it will place an error in the logfile and exit. Under normal circumstances, this shouldn't happen. If this error occurs frequently, then you can change the maximum amount of memory that the MDS uses. To be able to do this, you need enough physical memory in your computer. For an installation of the MDS that is used intensively, Metatude recomends at least 1 GB of memory.
Changing the maximum amount of used memory
Enter the command vm in the console to see the maximum amount of memory that the MDS will use. Enter the command vmc to change these settings. The changes you enter here will be placed in a config file and are permanent.