PCI Express® Performance Measurements
Application Notes
The serial point-to-point PCI Express technology supports up to 4 GB/s bandwidth per direction. Depending on the link width, the bandwidth scales from 250 MB/s to 4 GB/s per direction. But, this high theoretical bandwidth does not guarantee the overall performance will be optimal. Performance always depends on the efficiency of both devices on a PCI Express link. Parameters like payload size, flow control credit availability and different latencies strongly influence the overall result.
It’s not an easy job to predict the actual performance of a new device. The numerous input factors make it very difficult to find a precise estimate of the real-live performance.