Synergy User Manual and Tutorial. - THE CORE MEMORY

Synergy User Manual and Tutorial
Synergy Philosophy
Facilitating the best use of computing and networking resources for each application is
the key philosophy in Synergy. We advocate competitive resource sharing as opposed to
``cycle stealing.'' The tactic is to reduce processing time for each application. Multiple
running applications would fully exploit system resources. The realization of the
objectives, however, requires both quantitative analysis and highly efficient tools.
It is inevitable that parallel programming and debugging will be more time consuming
than single thread processing regardless how well the application programming interface
(API) is designed. The illusive parallel processing results taught us that we must have
quantitatively convincing reasons to processing an application in parallel before
committing to the potential expenses (programming, debugging and future maintenance.)
We use Timing Models to evaluate the potential speedups of a parallel program using
different processors and networking devices [13]. Timing models capture the orders of
timing costs for computing, communication, disk I/O and synchronization requirements.
We can quantitatively examine an application's speedup potential under various processor
and networking assumptions. The analysis results delineate the limit of hopes. When
applied to practice, timing models provide guidelines for processing grain selection and
experiment design.
Efficiency analysis showed that effective parallel processing should follow an
incremental coarse-to-fine grain refinement method. Processors can be added only if
there are unexplored parallelism, processors are available and the network is capable of
carrying the anticipated load. Hard-wiring programs to processors will only be efficient
for a few special applications with restricted input at the expense of programming
difficulties.
To improve performance, we took an application-oriented approach in the tool design.
Unlike conventional compilers and operating systems projects, we build tools to
customize a given processing environment for a given application. This customization
defines a new infrastructure among the pertinent compilers, operating systems and the
application for effective resource exploitation. Simultaneous execution of multiple
parallel applications permits exploiting available resources for all users. This makes the
networked processors a fairly real ``virtual supercomputer.''
An important advantage of the Synergy compiler-operating system-application
infrastructure is the higher level portability over existing systems. It allows written
parallel programs to adapt into any programming, processor and networking technologies
without compromising performance.
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