Supermicro AOC-SG-i4, Руководство пользователя

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4-5
Chapter 4: Linux Base Driver for PRO/1000 Family of Adapters
RxDescriptors
80-256 for 82542
and 82543-based
adapters
80-4096 for all
other supported
adapters
256
This value specifies the number of receive buffer
descriptors allocated by the driver. Increasing this
value allows the driver to buffer more incoming
packets, at the expense of increased system
memory utilization.
Each descriptor is 16 bytes. A receive buffer is also
allocated for each descriptor and can be either
2048, 4096, 8192, or 16384 bytes, depending on
the MTU setting. The maximum MTU size is 16110.
NOTE: MTU designates the frame size, and it only
needs to be set for Jumbo Frames. Depending on
the available system resources, the request for a
higher number of receive descriptors may be
denied. In this case, use a lower number.
RxIntDelay 0-65535 (0=off) 0
This value delays the generation of receive
interrupts in units of 1.024 microseconds. Receive
interrupt reduction can improve CPU efficiency if
properly tuned for specific network traffic.
Increasing this value adds extra latency to frame
reception and can end up decreasing the
throughput of TCP traffic. If the system is reporting
dropped receives, this value may be set too high,
causing the driver to run out of available receive
descriptors.
WARNING: When setting RxIntDelay to a value
other than 0 , adapters may hang (stop transmitting)
under certain network conditions. If this occurs a
NETDEV WATCHDOG message is logged in the
system event log. In addition, the controller is
automatically reset, restoring the network
connection. To eliminate the potential for the hang
ensure that
RxIntDelay is set to zero .
RxAbsIntDelay 0-65535 (0=off) 128
This value, in units of 1.024 microseconds, limits
the delay in which a receive interrupt is generated.
Useful only if
RxIntDelay is non-zero, this value
ensures that an interrupt is generated after the
initial packet is received within the set amount of
time. Proper tuning, along with
RxIntDelay , may
improve traffic throughput in specific network
conditions.
This parameter is supported only on 82540, 82545
and later adapters.
Speed 0, 10, 100, 1000 0
Speed forces the line speed to the specified value
in megabits per second (Mbps). If this parameter is
not specified or is set to 0 and the link partner is set
to auto-negotiate, the board will auto-detect the
correct speed.
Duplex must also be set when
Speed is set to either 10 or 100.
This parameter is supported only on adapters using
copper connections.
Table 4-1. Command Line Parameter Settings (Continued)
Parameter
Name Valid Range/
Settings Default Description