1. A multi-processor circuit, the circuit comprising: a plurality of processors, each having an addressing output; a plurality of independently addressable memory banks, each having an addressing input; a connection circuit coupled between the addressing outputs and the addressing inputs, and arranged to forward addresses from a combination of the processors to addressing inputs of memory banks selected by the addresses, the connection circuit providing for a conflict resolution scheme wherein at least one of the processors is associated with an associated one of the memory banks as an associated processor, the connection circuit being arranged to guarantee the associated processor a higher minimum guaranteed access frequency to said associated one of the memory banks than to a further one of the memory banks other than the associated one of the memory banks; a storage element for storing a threshold address for distinguishing between addresses that are mapped to according to respective mappings before and after said remapping; a defragmenter, arranged to detect data associated with a task running on the associated processor that is stored on the further one of the memory banks, to move said data to the associated one of the memory banks during execution of the task in response to said detection and to cause addressing of the data by the associated processor to be remapped from said further one of the memory banks to the associated one of the banks after said moving, wherein the defragmenter is arranged to: move a block of data items by moving respective data items for successive addresses in the block successively during execution of the task, and to cause the threshold address in said storage element to be updated each time when a successive one of the data items has been moved.