Realtime PCI Express monitoring for self adaptive reconfigurable systems

In this paper we introduce the concept for an embedded performance monitor of PCI Express links. This PCI Express Performance Monitor (PPM) enables the analysis of several properties (e.g. amount of available credits), without affecting the performance of the monitored link. By including a PPM in an embedded system it is possible to avoid the need for high cost PCI Express measurement and analyzing equipment. The concept was implemented on a rapid prototyping system to monitor several PCI Express links that connect an Intel Atom processor with an Altera Field Programmable Gate Array (FPGA). In addition we present a framework of functions, which makes it easy to use the utilization of a monitored PCI Express link as trigger condition for self adaptive systems.