37677833
An Open Monitoring System for Parallel and Distributed Programs
The on-line monitoring interface specification OMIS provides means for developing more powerful tool environments for parallel and distributed systems. It specifies the interaction between any tool and a monitoring system which is responsible for observing and manipulating the programs' execution. By having this well defined interface it is now possible to concurrently use several tools of possibly different developers with the same program run. The research group at LRR-TUM currently designs an OMIS compliant monitoring system for PVM running on workstation clusters. Tool developers can use this implementation to attach their own on-line tools to the system.
5417861
Load Management on Multiprocessor Systems
1 I n t r o d u c t i o n During the last years much research has been devoted to the development of multiprocessor systems. There are not only considerable advances in hardware architecture but also in the design and implementa t ion of software tools. Nevertheless, it is still easier to build a parallel machine than to use it efficiently. Two ma jo r types of parallel computers are available now: multiprocessor systems with shared memory and systems with distributed memory. Most of the problems concerning programming and running programs efficiently do not exist for shared memory systems due to the fact tha t these machines resemble monoprocessor systems with mult i tasking facilities. This paper completely concentrates on multiprocessors with distributed memory. Using systems with distributed memory usually makes program development and performance tuning of the programs very difficult. One severe problem is the load imbalance between processing nodes tha t may appear during runtime. Two approaches can be used to cope with this particular type of problem which can sometimes reduce the performance of a parallel system to that of a single monoprocessor: A static approach manages the distribution of processes to the processors before runt ime (usually called mapping) . In many cases this approach requires a priori knowledge about the behaviour of the program, i.e. execution t imes of the processes or precedence relations between them. If this a priori knowledge is not available, a dynamic approach is applied, where the distribution of processes happens during runtime of the program. This approach is referred to as load sharing or load balancing.
32939660
Bottleneck Detection in Parallel File Systems with Trace-Based Performance Monitoring
Today we recognize a high demand for powerful storage. In industry this issue is tackled either with large storage area networks, or by deploying parallel file systems on top of RAID systems or on smaller storage networks. The bigger the system gets the more important is the ability to analyze the performance and to identify bottlenecks in the architecture and the applications. 
 
We extended the performance monitor available in the parallel file system PVFS2 by including statistics of the server process and information of the system. Performance monitor data is available during runtime and the server process was modified to store this data in off-line traces suitable for post-mortem analysis. These values can be used to detect bottlenecks in the system. Some measured results demonstrate how these help to identify bottlenecks and may assists to rank the servers depending on their capabilities.
25210413
Performance Assessment of Parallel Spectral Analysis: Towards a Practical Performance Model for Parallel Medical Applications
To determine the need for a parallel computer on campus a committee of the Graduate Program in Computer Science surveyed selected Dartmouth College faculty and students in December and January We hope that the information in this report can be used by many groups on campus including the Computer Science graduate program and DAGS summer institute Kiewit s NH Supercomputer Initiative and by numerous researchers hoping to collaborate with people in other disciplines We found signi cant interest in parallel supercomputing on campus An on campus par allel supercomputing facility would not only support numerous courses and research projects but would provide a locus for intellectual activity in parallel computing encouraging interdisci plinary collaboration We believe that this report is a rst step in that direction All of the committee members can be reached by email at fullname Dartmouth edu where dots replace spaces in the name e g David Kotz Dartmouth edu Dartmouth Parallel Computer Needs January
17087246
Efficiently building on-line tools for distributed heterogeneous environments
Software development is getting more and more complex, especially within distributed middleware-based environments. A major drawback during the overall software development process is the lack of on-line tools, i.e. tools applied as soon as there is a running prototype of an application. The MIMO MIddleware MOnitor provides a solution to this problem by implementing a framework for an efficient development of on-line tools. 
 
This paper presents a methodology for developing on-line tools with MIMO. As an example scenario, we choose a distributed medical image reconstruction application, which represents a test case with high performance requirements. Our distributed, CORBA-based application is instrumented for being observed with MIMO and related tools. Additionally, load balancing mechanisms are integrated for further performance improvements. 
 
As a result, we obtain an integrated tool environment for observing and steering the image reconstruction application. By using our rapid tool development process, the integration of on-line tools shows to be very convenient and enables an efficient tool deployment.
9985094
A Universal Infrastructure for the Run-Time Monitoring of Parallel and Distributed Applications
On-line tools for parallel and distributed programs require a facility to observe and possibly manipulate the programs’ run-time behavior, a so called monitoring system. Currently, most tools use proprietary monitoring techniques that are incompatible to each other and usually apply only to specific target platforms. The On-line Monitoring Interface Specification (OMIS) is the first specification of a universal interface between different tools and a monitoring system, thus enabling interoperable, portable and uniform tool environments. The paper gives an introduction into the basic concepts of OMIS and presents the design and implementation of an OMIS compliant monitoring system (OCM).
38935360
Analyzing Metadata Performance in Distributed File Systems
The performance of metadata processing in large distributed file systems currently presents larger challenges than scaling of data throughput. The paper presents a novel, distributed benchmark called DMetabench for measuring the performance of metadata operations (e.g. file creation). DMetabench runs in environments with potentially thousands of nodes and allows an assessment of the scalability of metadata operations. Additionally, precise run-time performance data is preserved which allows for a better understanding of performance artifacts. Validation results from production file systems at the Leibniz Supercomputing Centre (LRZ) are provided and discussed. Possible applications of knowledge about metadata performance scaling include the choice of an optimal parallelization strategy for metadata-itensive workload in a specific runtime environment.
42724595
Standard-cell-based design methodology for high-performance support chips
We describe the methodology used for the design of a set of CMOS support chips used in the IBM S/390® Parallel Enterprise Server Generations 3 and 4. The logic design is based on functional units, and the majority of the logic is implemented by standard cell elements placed and routed flat, using timing-driven techniques. Custom library elements are used wherever needed for performance reasons. Using this approach, a density has been achieved that is comparable to those of contemporary custom designs, combined with very attractive turnaround times.
6349430
A flat, timing-driven design system for a high-performance CMOS processor chipset
We describe the methodology used for the design of the CMOS processor chipset used in the IBM S/390 Parallel Enterprise Server-Generation 3. The majority of the logic is implemented by standard cell elements placed and routed flat, using timing-driven techniques. The result is a globally optimized solution without artificial floorplan boundaries. We show that the density in terms of transistors per mm/sup 2/ is comparable to the most advanced custom designs and that the impact of interconnect delay on the cycle time is very small. Compared to custom design, this approach offers excellent turn-around-time and considerably reduces overall effort.