PCIe adapters on POWER processor-based systems that take advantage of 64-bit DMA
Peripheral Component Interconnect Express® (PCIe) adapters that are supported for POWER® processor-based systems vary in their ability to take advantage of 64-bit direct memory access (DMA) with Linux®.
IBM® POWER processor-based systems that are running Linux support various PCIe adapters. The type of PCIe adapters depend on the system and whether it supports 64-bit DMA.
The following list provides a description of the recommendations mentioned in the Recommendation for placing the adapter
into a 64-bit DMA-capable slot table.
- No benefit
- The adapter or driver does not recognize the capability, or the adapter is not a high-performance adapter. For example, a modem.
- Optional; possible benefit
- The adapter or driver recognizes the capability and enables it. Depending on the workload, your system might or might not see a performance benefit when the adapter is placed in a 64-bit DMA capable slot.
- Recommended; likely benefit
- The adapter or driver recognizes the capability and enables it. Depending on the workload, efficiency and performance of your system might improve when the adapter is placed in a 64-bit DMA capable slot.
- Highly recommended
- The adapter or driver recognizes the capability and enables it. Efficiency and performance of your system might improve when the adapter is placed in a 64-bit DMA capable slot.
- Required
- The adapter must be placed in a 64-bit DMA capable slot, or functional issues might occur.
The following table lists PCIe adapter types that are supported for the Linux operating system that is running on POWER processor-based systems and recommendation for placing the adapter into a 64-bit
DMA-capable slots:
| Adapter Type | Recommendation for placing the adapter into a 64-bit DMA-capable slot |
| 1Gb ethernet | Optional; possible benefit |
| 10Gb / 40Gb / 100Gb ethernet | Recommended; likely benefit |
| Infiniband or RoCE | Required |
| NVMe | Highly Recommended; likely benefit |
| SAS | Optional; possible benefit |
| Fibre Channel | Optional; possible benefit |
| NVMf-FC | Recommended; likely benefit |
| Graphics | No benefit |
| USB | No benefit |
| Async | No benefit |