Garbage Collection Time Research Articles

A multiprocessing system for the direct execution of LISP

Current implementations were found to be impractical for airborne use due to LISP's incompatability with conventional computer architectures. Direct execution of LISP with tasks distributed between three processors, seemed to be a workable solution. The language was analyzed, and a special token was devised, using a descriptor with a single pointer. Through careful distribution of responsibilities, control and data flow between the processors was minimized. Significant memory savings resulted from ASCII storage and real time garbage collection. A simulation was used to help estimate execution times and showed a factor of 50 to 100 increase in speed. Thus, through the direct execution of LISP by a multiprocessing system, Computer-Aided Decision-Making could be implimented to enhance the safety of flight operations.

A multiprocessing system for the direct execution of LISP

Current implementations were found to be impractical for airborne use due to LISP's incompatability with conventional computer architectures. Direct execution of LISP with tasks distributed between three processors, seemed to be a workable solution. The language was analyzed, and a special token was devised, using a descriptor with a single pointer. Through careful distribution of responsibilities, control and data flow between the processors was minimized. Significant memory savings resulted from ASCII storage and real time garbage collection. A simulation was used to help estimate execution times and showed a factor of 50 to 100 increase in speed. Thus, through the direct execution of LISP by a multiprocessing system, Computer-Aided Decision-Making could be implimented to enhance the safety of flight operations.

A multiprocessing system for the direct execution of LISP

Current implementations were found to be impractical for airborne use due to LISP's incompatability with conventional computer architectures. Direct execution of LISP with tasks distributed between three processors, seemed to be a workable solution. The language was analyzed, and a special token was devised, using a descriptor with a single pointer. Through careful distribution of responsibilities, control and data flow between the processors was minimized. Significant memory savings resulted from ASCII storage and real time garbage collection. A simulation was used to help estimate execution times and showed a factor of 50 to 100 increase in speed. Thus, through the direct execution of LISP by a multiprocessing system, Computer-Aided Decision-Making could be implimented to enhance the safety of flight operations.

Analysis of an algorithm for real time garbage collection

A real time garbage collection system avoids suspending the operations of a list processor for the long times that garbage collection normally requires by performing garbage collection on a second processor in parallel with list processing operations, or on a single processor time-shared with them. Algorithms for recovering discarded list structures in this manner are presented and analyzed to determine sufficient conditions under which the list processor never needs to wait on the collector. These techniques are shown to require at most twice as much processing power as regular garbage collectors, if they are used efficiently. The average behavior of the program is shown to be very nearly equal to the worst-case performance, so that the sufficient conditions are also suitable for measuring the typical behavior of the algorithm.