From: Olga Shern <ol...@mellanox.com> Describe how applications can benefit from CQE compression.
Signed-off-by: Olga Shern <olgas at mellanox.com> Signed-off-by: Adrien Mazarguil <adrien.mazarguil at 6wind.com> --- doc/guides/nics/mlx5.rst | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst index 2d68914..eb8c042 100644 --- a/doc/guides/nics/mlx5.rst +++ b/doc/guides/nics/mlx5.rst @@ -130,6 +130,19 @@ These options can be modified in the ``.config`` file. This value is always 1 for RX queues since they use a single MP. +Environment variables +~~~~~~~~~~~~~~~~~~~~~ + +- ``MLX5_ENABLE_CQE_COMPRESSION`` + + A nonzero value lets ConnectX-4 return smaller completion entries to + improve performance when PCI backpressure is detected. It is most useful + for scenarios involving heavy traffic on many queues. + + Since the additional software logic necessary to handle this mode can + lower performance when there is no backpressure, it is not enabled by + default. + Run-time configuration ~~~~~~~~~~~~~~~~~~~~~~ -- 2.1.0
