[petsc-users] MatSetValues error with ViennaCL types

[Karl Rupp]

>> I thought newer NVIDIA cards had integrated circuits, not using PCI
>> anymore, still the same case?
> 
> NVLink is much faster than PCI, but it's still a bus that is slower (and
> higher latency) than aggregate DDR, though there are open questions
> about how much message packing (for example) should take place on GPU
> versus CPU.

To add: NVLink has higher bandwidth, but as far as I know it has about 
the same latency. That is, if you send just a few (kilo-)bytes around, 
you'll see the same latency problems as with PCI-Express.

Best regards,
Karli