Mayfly: A general-purpose, scalable, parallel processing architecture

Abstract

Abstract. The Mayfly is a scalable general-purpose parallel processing system being designed at HP Laboratories, in collaboration with colleagues at the University of Utah. The system is intended to efficiently support parallel variants of modern programming languages such as Lisp, Prolog, and Object Oriented Programming models. These languages impose a common requirement on the hardware platform to support dynamic system needs such as runtime type checking and dynamic storage management. The main programming language for the Mayfly is a concurrent dialect of Scheme. The system is based on a distributed-memory model, and communication between processing elements is supported by message passing. The initial prototype of Mayfly will consist of 19 identical processing elements interconnected in a hexagonal mesh structure. In order to achieve the goal of scalable performance, each processing element is a parallel processor as well, which permits the application code, runtime operating system, and communication to all run in parallel. A 7 processing element subset of the prototype is presently operational. This paper describes the hardware architecture after a brief background synopsis of the software system structure. I n t r o d u c t i o nThe goal of the M a y f l y effort was to produce a general-purpose scalable parallel processor. More specifically we sought to produce a machine that: Would achieve increased performance, primarily through parallelism, for both numeric and symbolic computations.Would exhibit a reasonable performance improvement as the number of processing elements in the system was increased. The argument of what constitutes reasonable performance scaling is difficult to precisely quantify and subsequently this issue will be addressed in more detail, but it is clear that logarithmic performance scaling is not generally cost-effective, and that achieving linear speedup over a wide range of applications would be ideal but perhaps impossible to attain.

pp-mess-sim: a flexible and extensible simulator for evaluating multicomputer networks

“…2, the default best-effort traffic is assigned dimension-ordered routing, which requires a packet to complete all hops in one direction before proceeding to the next dimension; in contrast, line 32 specifies that timeconstrained packets consider their minimal-path output links in a random order. In addition to these two selection functions, Net can rank outgoing links according to how much further the packet must travel in each direction; this link ordering improves the packet's chance of considering multiple outgoing links at future nodes in its route [36], [37]. For example, if a packet is traveling from node (4, 3) to node (6, 10) in a square mesh, the diagonal selection function would recommend traveling in the y-direction, instead of the x-direction, if both links are idle.…”

Maygen: A Symbolic Debugger Generation System

“…Compiled C programs are processed by the Mayfly architecture [Dav92]. The Mayfly, developed at Hewlett Packard Laboratories, serves as a back-end processor for a Hewlett Packard Series 800 workstation.…”

Arrowhead and Diamond Diameters

“…The grid representation of the graph is a hexagonal torus with D circular rings of length 6D arranged around a central node. Incidentally, this family of "honeycombs" H n was encountered elsewhere, arising in various projects such as FAIM-1 [10], Mayfly [11], HARTS [12] and more recently with the EJ [13] networks [14].…”