MLX4DV(7)             Miscellaneous Information Manual             MLX4DV(7)

NAME         top

       mlx4dv - Direct verbs for mlx4 devices
       This  is low level access to mlx4 devices to perform data path opera‐
       tions, without general branching performed by ibv_post_send(3).

DESCRIPTION         top

       The libibverbs API is an abstract one. It is agnostic to any
       underlying provider specific implementation. While this abstraction
       has the advantage of user applications portability it has a
       performance penalty. For some applications optimizing performance is
       more important than portability.

       The mlx4 direct verbs API is intended for such applications.  It
       exposes mlx4 specific low level data path (send/receive/completion)
       operations, allowing the application to bypass the libibverbs data
       path API.

       This interface consists from one hardware specific header file with
       relevant inline functions and conversion logic from ibverbs
       structures to mlx4 specific structures.

       The direct include of mlx4dv.h together with linkage to mlx4 library
       will allow usage of this new interface.

       Once an application uses the direct flow the locking scheme is fully
       managed by itself. There is an expectation that no mixed flows in the
       data path for both direct/non-direct access will be by same

NOTES         top

SEE ALSO         top

       ibv_post_send(3), verbs(7)

AUTHORS         top

       Maor Gottlieb <>

COLOPHON         top

       This page is part of the rdma-core (RDMA Core Userspace Libraries and
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1.0.0                            2017-04-19                        MLX4DV(7)

Pages that refer to this page: mlx4dv_init_obj(3)mlx4dv_query_device(3)