I’m running Toolkit 8.0 on a Linux Mint machine with driver 367.57, and noticed that while running my application on two GTX 1080 cards, one card had a typical DMA tranfer rate of around 6GB/s, but the other card seemed to only reach about 1.4GB/s. The cards are running identical code. Furthermore a yellow triangle enclosing a “!” appears next to the slower car’s throughput figures. Both cards correctly show the CPU memory as pinned.
There is no explanation I can find that shows what the yellow warning means (other than the obvious “this seems too slow”), and no guidance on how to fix it. Is it simply a difference due to the PCIE bandwidths associated with each card position?