Performance Tuning of Multithreaded Applications for Different Multiprocessor Platforms

Performance tuning of a parallel application is often hard. The use of standards, such as POSIX threads, makes it possible to move a multithreaded application from one platform to another. Doing performance tuning for many platforms are even tougher since the implemen-tation of the standards may vary on different operating systems. The developer need tools for analysing how the application will behave on different operating systems in order to do ade-quate performance tuning. In this paper we present a technique based on cross-simulation that will solve the issues above. The technique uses a monitored execution of a multithreaded application on a single processor workstation running the Solaris operating system. Then the technique, which has been implemented in a tool, simulates a multiprocessor with an arbitrary number of proces-sors running either Solaris or Linux. The tool then displays the behaviour of the application on the selected target configuration. Validation, using a subset of the SPLASH-2 benchmark suite, shows that the tool predicts speed-ups correctly. The average error in the predicted speed-up when simulating Linux is 5.8%. All this can be done using the ordinary Solaris workstation on the developer’s desk, without even having a multiprocessor. 1