1. A Solution for the Multiple Writer Problem in Shared Memory Multiprocessors: Anticipated Intention to Commit in Adaptive Environment Confidential! Veljko Milutinovic, Fellow of the IEEE vm@etf.bg.ac.yu

2. The Best Method to Present Research Results 1. Introduction 2. Problem Statement 3. Existing Solutions 4. Essence of the Proposed Solution 5. Conditions and Assumptions 6. Details 7. Modelling 8. Analysis 9. Conclusions 10. References

3. 1. Introduction

4. 2. Problem Statement: MRMW

5. 3. Existing Solutions The BEST current MRMW solution comes from Stanford professor Kunle Olokotun: Two-Phase Commit The BEST current TMS/SMT solution comes from Barcelona professor Mateo Valero: Microsoft-Intel UPC

6. 4. Essence of the Proposed Approach Major improvements of our approach: a. Includes a timer b. Includes an anticipatory action (Intention to Commit can be executed before the moment when a process is actually ready to commit) c. Imlies the usage of SMT (Simultaneous Multi Threading), so the process can keep busy, while waiting for the commit activity to complete. Monitors and adaptivity

7. 5. Conditions and Assumptions Conditions: a. Size of MCM unit b. Processors vs processes and SMT c. Worst case delays in SMP vs DSM Assumptions: a. False sharing b. Add-on to a directory scheme c. System limits

8. 6. Details Intention to Commit a. Vector of starting MCM unit addresses b. Vector of shared data involved c. Timer activated Counter Interrupt a. No formal conflict b. Yes formal conflict; no essential conflict c. Both formal and essential conflict Adaptive Priorities Adaptive Abort vs Resume Adaptive SMT

9. 7. Analysis System Modelling, Performance Analysis, Complexity Analysis M5 GeneralSimulators vs UPC MareNostrum Microsoft vs Intel

10. 8. Conclusion and References