Memory Window (MW)

Memory Window allows the application to have more flexible control over remote access to its memory. It is available only on physical functions or native machines. The two types of Memory Windows supported are: type 1 and type 2B.

Memory Window is intended for situations where the application wants to:

  • Grant and revoke remote access rights to a registered region in a dynamic fashion with less of a performance penalty.

  • Grant different remote access rights to different remote agents and/or grant those rights over different ranges within registered region.

Experimental Verbs

RDMA-Core

Verbs

ibv_exp_bind_mw

ibv_bind_mw

ibv_exp_post_send

bind_mw

ibv_wr_bind_mw

ibv_exp_reg_mr

IBV_EXP_ACCESS_MW_BIND

ibv_reg_mr

IBV_ACCESS_MW_BIND

Capabilities and Device Attributes

IBV_EXP_DEVICE_MEM_WINDOW

IBV_DEVICE_MEM_WINDOW

IBV_EXP_DEVICE_MW_TYPE_2A

IBV_DEVICE_MEM_WINDOW_TYPE_2A

IBV_EXP_DEVICE_MW_TYPE_2B

IBV_DEVICE_MEM_WINDOW_TYPE_2B

IBV_DEVICE_MEM_MGT_EXTENSIONS

Environmental Variables

MLX5_SHUT_UP_MW

In RDMA-Core, it is possible to not use MW feature with the new post send API (ibv_posr_wr)

© Copyright 2023, NVIDIA. Last updated on Sep 8, 2023.