Partial FPGA Rearrangement by Local Repacking

Partial rearrangement of executing tasks has been proposed as a means of alleviating the fragmentation of free logic elements that occurs on space--shared run--time reconfigurable FPGA systems. In this paper, we present and assess a new solution to this strategy. Local repacking of executing tasks aims to free sufficient contiguous resources for the next waiting task so as to minimize allocation and execution delays. Heuristics for the NP--hard problems of identifying and scheduling optimal task rearrangements are described and assessed by comparison with known methods. 1 Introduction Partial configuration and context switching are two features of current FPGAs that permit efficient implementation of run--time reconfiguration. Partial reconfiguration has been variously used to recycle resources that are not currently used for circuits that are currently needed. A good example of this technique is the DISC system, which makes use of a well--defined global context to implement relocat..