Qlogic FastLinQ 3400 Series, User Manual

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5–Linux Driver Software
Setting Values for Optional Properties
36 83840-546-00 E
dropless_fc
The dropless_fc parameter can be used to enable a complementary flow control
mechanism on 8400/3400 Series adapters. The default flow control mechanism is
to send pause frames when the on-chip buffer (BRB) is reaching a certain level of
occupancy. This is a performance targeted flow control mechanism. On
8400/3400 Series adapters, one can enable another flow control mechanism to
send pause frames, where one of the host buffers (when in RSS mode) are
exhausted.
This is a zero packet drop targeted flow control mechanism.
Set the dropless_fc parameter to 1 to enable the dropless flow control
mechanism feature on all 8400/3400 Series adapters in the system.
insmod bnx2x.ko dropless_fc=1
or
modprobe bnx2x dropless_fc=1
disable_iscsi_ooo
The disable_iscsi_ooo parameter is to disable the allocation of the iSCSI TCP
Out-of-Order (OOO) reception resources, specifically for VMware for low-memory
systems.
multi_mode
The optional parameter multi_mode is for use on systems that support
multi-queue networking. Multi-queue networking on the receive side depends only
on MSI-X capability of the system, multi-queue networking on the transmit side is
supported only on kernels starting from 2.6.27. By default,
multi_mode parameter
is set to 1. Thus, on kernels up to 2.6.26, the driver will allocate on the receive
side one queue per-CPU and on the transmit side only one queue. On kernels
starting from 2.6.27, the driver will allocate on both receive and transmit sides,
one queue per-CPU. In any case, the number of allocated queues will be limited
by number of queues supported by hardware.
The multi_mode optional parameter can also be used to enable SAFC (Service
Aware Flow Control) by differentiating the traffic to up to 3 CoS (Class of Service)
in the hardware according to the VLAN PRI value or according to the IP DSCP
value (least 3 bits).
num_queues
The optional parameter num_queues may be used to set the number of queues
when multi_mode is set to 1 and interrupt mode is MSI-X. If interrupt mode is
different than MSI-X (see int_mode ), the number of queues will be set to 1,
discarding the value of this parameter.