Hi Ravi, > > Hi, > > The reason I am asking I because I have tried different combinations of > scalar and vector Tx and Rx processing for both IXGBE and I40E with > following results > > 1. Vector Rx and Vector Tx gives best performance but can only support > packet size of less than or equal to 2048 bytes > > 2. Scalar Rx and Scalar Tx works for all packet size but with degraded > performance > > 3. Vector Rx and Scalar Tx (with certain PMD configuration) works fine > (performance doesn't meet '1') but it has an inherent bug for packet size > 8192 bytes as PMD stops packet processing > > From the code I see both IXGBE and I40E can support scattered vector Rx, I > am curious to know any obvious reasons scattered vector Tx support is left > out and does it make sense to implement it? > > If it makes sense to implement scattered vector Tx and Intel team hasn't > worked on it I would like to make an attempt at it so kindly let me know. >
Yes, right now there is a tradeoff - simple TX functions (both vector and scalar) are much faster than full-featured TX function, but don't support any TX offloads or multi-segs. If you'd like to provide a patch that would add some TX offloads to the simple path without any performance degradation or either a patch that would improve performance of full-featured TX function - I am pretty sure such patches would be welcomed. Konstantin
