A hybrid performance monitor developed for MSPARC, a mesh-connected, message-passing multicomputer, is described. The development of the hybrid performance monitor was a cross-disciplinary enterprise requiring custom hardware and a range of software support including monitor code, driver interfaces, probe history acquisition and processing, graphical display, and application probe injection. Programmable hardware was designed to unobtrusively collect events on each node and maintain their accurate chronological order. This distributed collection system was coupled by its independent network to a central monitor where data selection and presentation techniques played an important role in the visualization of the parallel system's execution. >

https://ieeexplore.ieee.org/iel2/617/5226/00202424.pdf

A performance monitor for the MSPARC multicomputer

The author discusses development of a real-time monitoring environment to provide distributed programmers with valuable information about an executing program as events occur. Of particular importance is design and implementation of analysis software which accepts user requests, queries and receives event histories from the instrumentation system, and provides sufficient program abstractions to support graphical displays and metric evaluations of execution progress. The analysis software has been named DECIPHER. The DECIPHER distributed debugging system is described. The primary obstacle involves organizing and managing voluminous event histories in real-time. Both efficient organization and data management are crucial to effectiveness and accuracy. >

Organization and management of distributed execution event histories for real-time debugging

The MSPARC multicomputer uses processor-based monitoring hardware and probe acquisition software for instrumentation purposes. The authors give an overview of the monitor system and design considerations regarding the probe software. Each node of the mesh connected MSPARC consists of a numerical element and a communications board used to pass messages via custom routers located on a backplane. In addition to the message-passing circuitry, the communications board also contains the instrumentation and monitoring hardware. The monitor and its separate interconnection network are used to assist in application performance monitoring, program design, hardware and software debugging, and hardware analysis. Performance data are transferred from an application program to the monitor system in the form of software probes. The software provides initialization, probe processing, communications, and debug capabilities for a monitor node. >

D.H. Linder

Papers

Probe acquisition for the MSPARC hybrid monitor