Saturday, March 11, 2017 1:14 AM, Yongseok Koh: > Enhanced multi-packet send mode is newly introduced for ConnectX-5 > families of adaptors. > > Signed-off-by: Yongseok Koh <ys...@mellanox.com> > --- > doc/guides/nics/mlx5.rst | 31 +++++++++++++++++++++++++++---- > 1 file changed, 27 insertions(+), 4 deletions(-) > > diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst index > 41f3a472e..0783aebdd 100644 > --- a/doc/guides/nics/mlx5.rst > +++ b/doc/guides/nics/mlx5.rst > @@ -183,10 +183,17 @@ Run-time configuration > > - ``txq_mpw_en`` parameter [int] > > - A nonzero value enables multi-packet send. This feature allows the TX > - burst function to pack up to five packets in two descriptors in order to > - save PCI bandwidth and improve performance at the cost of a slightly > - higher CPU usage. > + A nonzero value enables multi-packet send (MPS) for ConnectX-4 Lx and > + enhanced multi-packet send (Enhanced MPS) for ConnectX-5. MPS allows > + the TX burst function to pack up multiple packets in a single > + descriptor session in order to save PCI bandwidth and improve > + performance at the cost of a slightly higher CPU usage. When > + ``txq_inline`` is set along with ``txq_mpw_en``, TX burst function > + tries to copy entire packet data on to TX descriptor instead of > + including pointer of packet only if there is enough room remained in > + the descriptor. ``txq_inline`` sets per-descriptor space for either > + pointers or inlined packets. In addition, Enhanced MPS supports > + hybrid mode - mixing inlined packets and pointers in the same descriptor. > > This option cannot be used in conjunction with ``tso`` below. When ``tso`` > is set, ``txq_mpw_en`` is disabled. > @@ -194,6 +201,22 @@ Run-time configuration > It is currently only supported on the ConnectX-4 Lx and ConnectX-5 > families of adapters. Enabled by default. > > +- ``txq_mpw_hdr_dseg_en`` parameter [int] > + > + A nonzero value enables including two pointers in the first block of > + TX descriptor. This can be used to lessen CPU load for memory copy. > + > + Effective only when Enhanced MPS is supported. Disabled by default. > + > +- ``txq_max_inline_len`` parameter [int] > + > + Maximum size of packet to be inlined. This limits the size of packet > + to be inlined. If the size of a packet is larger than configured > + value, the packet isn't inlined even though there's enough space > + remained in the descriptor. Instead, the packet is included with pointer. > + > + Effective only when Enhanced MPS is supported. The default value is 256. > + > - ``tso`` parameter [int] > > A nonzero value enables hardware TSO. > --
Acked-by: Shahaf Shuler <shah...@mellanox.com> > 2.11.0
