NAME

SYNOPSIS

Or, to load the driver as a module at boot, place the following line in loader.conf(5):

ntb_transport_load="YES"

The following tunables are settable from the loader(8):

hw.ntb_transport.debug_level

Driver debug level. The default value is 0, higher means more verbose.

hw.ntb_transport.max_mw_size

Limits maximum memory window usage. Allocation of big physically contiguous memory buffer may be a problem, while too big buffers makes no much sense for low latency network interface.

hint.ntb_transport.X.config

Configures a set of the transport consumers, separated by commas. Each consumer can be configured as: "[<name>][:<queues>]", where: name is a name of the driver to attach (empty means any), queues is a number of queues to allocate (empty means automatic). The default configuration is empty string, which means single consumer with one queue per memory window, allowing any driver to attach.

hint.ntb_transport.X.compact

Non-zero value enables compact version of scratchpad protocol, using half as many registers. Enabled automatically if there is not enough registers to negotiate all available memory windows. The compact version does not support memory windows of 4GB and above.

DESCRIPTION

Each ntb_transport require from underlying ntb instance:

• 1 or more memory windows;
• 6 scratchpads, plus 2 more for each additional memory window, or 3 plus 1 in case of compact protocol;
• 1 doorbell for each memory window or configured queue.

SEE ALSO

AUTHORS