Dynamic Memory Allocation Failure

FIT2D uses dynamic memory (or virtual memory) allocation to allow as much flexibility as possible in the size of data that can be treated. This has obvious advantages, but also a disadvantage. 2-D dimensional data (images) from modern detector systems can be very large, so the demands of FIT2D for memory allocation can be similarly large. Users are recommended to try to use the minimum of memory necessary for their data. At start-up the initial size of program arrays is set.

If at any stage during the running of FIT2D the user gets a message that memory allocated has failed, it must be assumed that the previous command has failed.

The amount of memory available on a computer system varies as the demands of other uses and processes changes. Thus, a program which works one day, may fail another. The available memory is determined by system parameters, so see your system administrator if there are persistent problems.

It should be noted that the memory does not have to be RAM, as modern computer systems allow hard-disk files to used as ``virtual memory''. However, if sufficient RAM is not available, a performance degradation will be noticed.