On 07/05/2013 01:35, Alexander Duyck wrote:
The Tx path ends up taking a performance hit if IOMMU is enabled. It just isn't as severe due to things like TSO.
In testing done by some Mellanox folks I think they see major penalty on the RX side, but hardly
nothing on the TX side, I'll check that.
One way to work around the performance penalty is to allocate bounce buffers and just leave them static mapped. Then you can simply memcpy the data to the buffers and avoid the locking overhead of allocating/freeing IOMMU resources. It consumes more memory but works around the IOMMU limitations.
I don't think can be applicable approach to fast networking/storage drivers. Or. _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
