Difference between revisions of "Talk:POWER9 Hardware Compatibility List/PCIe Devices"
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(Fixed 40 bits are 1 TB (not 128 GB)) |
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> rendering them incapable of addressing host memory which lies above address 240. (Firmware patches to work around this are pending.) | > rendering them incapable of addressing host memory which lies above address 240. (Firmware patches to work around this are pending.) | ||
| − | 2^40 means | + | 2^40 means 1 TB of RAM. Does this mean I can still use this these PCIe devices without any unwanted side-effects if I do not have more than 128 GB RAM? |
Latest revision as of 10:21, 2 February 2020
What is the impact of incomplete PCIe address space (eg. 40 instead of 64 bits)?
This page says:
> Incomplete memory addressing support. The PCIe architecture specifies a 64-bit address space. > Some I/O devices try to economize on this by only implementing e.g. 40 bits for their addressing, > rendering them incapable of addressing host memory which lies above address 240. (Firmware patches to work around this are pending.)
2^40 means 1 TB of RAM. Does this mean I can still use this these PCIe devices without any unwanted side-effects if I do not have more than 128 GB RAM?
