| 1. |
|
|
| 2. |
- Björnfot, Lars, et al.
(author)
-
Distributed Run-Time System, a Protocol for Ada
- 1993
-
In: Proc. Ada-Europe'93, LNCS 688. - Berlin, Heidelberg : Springer Berlin Heidelberg. ; , s. 249-263
-
Conference paper (other academic/artistic)abstract
- The requirements and specification of a protocol for low level communication between the run-time systems in a distributed Ada environment is presented. This allows an Ada system to be separated into software resources and run-time controllers. Calls to the local run-time system of a node, concerning task management, are transformed into remote calls to the controller, that schedules all tasks in the application. The calls to the run-time system together with all messages, requests and replies, that are triggered as a consequence, are described. The controller will be implemented in hardware separate from the processors. Communication between processors and controllers are by means of high speed (Gigabit) networks. In the proposed system, partitioning and distribution of Ada programs can fully utilize the inherent and strong type checking in Ada.
|
|
| 3. |
- Björnfot, Lars, et al.
(author)
-
Distribution of Tasks Within a Centrally Scheduled Local Area Network
- 1994
-
In: Proc. Ada-Europe'94, LNCS 887. - Berlin, Heidelberg : Springer Berlin Heidelberg. ; , s. 421-432
-
Conference paper (other academic/artistic)abstract
- Distribution of a single Ada program on a local area network is accomplished by partitioning the run-time system into two parts. A central scheduling module is responsible for task management. Distributed run-time executives handle context switches and remote entry calls; however all activities are supervised by the scheduler. The scheduler can be implemented in hardware in order to achieve high efficiency. A network based on optical fibers is necessary due to the high speed required for system calls. Asynchronous Transfer Mode is suggested as the protocol for the communication. We describe an implementation of the divided run-time system on an Ethernet network, using MC68030-based micro computers as targets and an Ada program executing on a Rational host as the scheduler.
|
|
| 4. |
- Brorsson, Mats
(author)
-
Local vs. global memory in the IBM RP3 : experiments and performance modelling
- 1991
-
Conference paper (peer-reviewed)abstract
- A number of experiments regarding the placement of instructions, private data and shared data in the Non-Uniform-Memory-Access multiprocessor, RP3, have been performed. Three scientific/mathematical workloads have been used in the experiments, and the results have been modelled in a simple performance model which takes linear contention into consideration. The results indicate that it can very well be feasible not to have memory local to the processors in RP3-like architectures. There seems to be a trade-off between the effort spent in the design on the memory system and the interconnection network and the use of local memory which can be costly in terms of prohibited process migration and more complicated software management.
|
|
| 5. |
- Brorsson, Mats, et al.
(author)
-
Modelling accesses to migratory and producer-consumer characterised data in a shared memory multiprocessor
- 1994
-
Conference paper (peer-reviewed)abstract
- Directory-based, write-invalidate cache coherence protocols are effective in reducing latencies to the memory but suffer from cache misses due to coherence actions. It is therefore important to understand the nature of data sharing causing misses for this class of protocols. We identify a set of parameters that characterises the accesses to migratory and producer-consumer data in sufficient detail so as to predict the number of cache misses in directory-based, write-invalidate protocols. We show that the parameters can be extracted from real programs and used as input to a reference generator that artificially generates a stream of references causing accurate estimates of cold, coherence and directory replacement misses, compared to the program itself.
|
|
| 6. |
- Brorsson, Mats, et al.
(author)
-
Modelling accesses to stationary data in a shared memory multiprocessor
- 1994
-
Conference paper (peer-reviewed)abstract
- Cache misses due to coherence and directory maintenance is a major reason for poor performance in shared memory multiprocessors. We show that the relationship between a particular access pattern and cache miss ratios for a class of directory-based, write-invalidate cache coherence protocols can be characterised in a small set of parameters. In order to do this, a reference generator has been designed that, based on parameters automatically extracted from a program, can artificially generate a reference stream that results in the same cold, coherence and directory replacement miss ratios as an execution of the program.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Duchamp, Daniel J., et al.
(author)
-
Software technology for wireless mobile computing
- 1991
-
In: IEEE Network. - : IEEE. - 0890-8044 .- 1558-156X. ; 5:6, s. 12-18
-
Journal article (peer-reviewed)abstract
- Some of the possibilities and requirements for mobile computing on wireless local area networks (LANs) are discussed from the systems software viewpoint. The design of the Student Electronic Notebook (SEN) is sketched to provide a partial catalog of problems in building a real system for wireless mobile computing. This project was initiated to investigate the potential of wireless mobile computing to reshape education. Some of the key directions for research in software technology for wireless, mobile computing are examined. Some of the authors' experience with wireless LANs is related.
|
|
| 10. |
|
|
