PCI-DDC application programming interface: Performance in user-level messaging

Abstract

Many programming interfaces which deal with peripherals (especially network peripherals) need to access the critical resources of the operating system, and system calls (or drivers) are generally used. Unfortunately, t he time spent on such system calls is often greater than those requested for the operations themselves. In the case of the MPC machine, m ost of these operations do not need an intervention from the system and resources may be available from user applications. Our programming interface provides different levels of integration in the kernel depending on the security and the performance expected by the administrator. This article presents PAPI user-level performance.