68f20d948c
- Update the Intel Wired LAN documentation with the latest URL for ethtool. - replace "Ethtool" with "ethtool" Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Tested-by: Emil Tantilov <emil.s.tantilov@intel.com>
306 lines
12 KiB
Text
306 lines
12 KiB
Text
Linux* Driver for Intel(R) Network Connection
|
|
=============================================
|
|
|
|
Intel Gigabit Linux driver.
|
|
Copyright(c) 1999 - 2010 Intel Corporation.
|
|
|
|
Contents
|
|
========
|
|
|
|
- Identifying Your Adapter
|
|
- Command Line Parameters
|
|
- Additional Configurations
|
|
- Support
|
|
|
|
Identifying Your Adapter
|
|
========================
|
|
|
|
The e1000e driver supports all PCI Express Intel(R) Gigabit Network
|
|
Connections, except those that are 82575, 82576 and 82580-based*.
|
|
|
|
* NOTE: The Intel(R) PRO/1000 P Dual Port Server Adapter is supported by
|
|
the e1000 driver, not the e1000e driver due to the 82546 part being used
|
|
behind a PCI Express bridge.
|
|
|
|
For more information on how to identify your adapter, go to the Adapter &
|
|
Driver ID Guide at:
|
|
|
|
http://support.intel.com/support/go/network/adapter/idguide.htm
|
|
|
|
For the latest Intel network drivers for Linux, refer to the following
|
|
website. In the search field, enter your adapter name or type, or use the
|
|
networking link on the left to search for your adapter:
|
|
|
|
http://support.intel.com/support/go/network/adapter/home.htm
|
|
|
|
Command Line Parameters
|
|
=======================
|
|
|
|
The default value for each parameter is generally the recommended setting,
|
|
unless otherwise noted.
|
|
|
|
NOTES: For more information about the InterruptThrottleRate,
|
|
RxIntDelay, TxIntDelay, RxAbsIntDelay, and TxAbsIntDelay
|
|
parameters, see the application note at:
|
|
http://www.intel.com/design/network/applnots/ap450.htm
|
|
|
|
InterruptThrottleRate
|
|
---------------------
|
|
Valid Range: 0,1,3,4,100-100000 (0=off, 1=dynamic, 3=dynamic conservative,
|
|
4=simplified balancing)
|
|
Default Value: 3
|
|
|
|
The driver can limit the amount of interrupts per second that the adapter
|
|
will generate for incoming packets. It does this by writing a value to the
|
|
adapter that is based on the maximum amount of interrupts that the adapter
|
|
will generate per second.
|
|
|
|
Setting InterruptThrottleRate to a value greater or equal to 100
|
|
will program the adapter to send out a maximum of that many interrupts
|
|
per second, even if more packets have come in. This reduces interrupt
|
|
load on the system and can lower CPU utilization under heavy load,
|
|
but will increase latency as packets are not processed as quickly.
|
|
|
|
The default behaviour of the driver previously assumed a static
|
|
InterruptThrottleRate value of 8000, providing a good fallback value for
|
|
all traffic types, but lacking in small packet performance and latency.
|
|
The hardware can handle many more small packets per second however, and
|
|
for this reason an adaptive interrupt moderation algorithm was implemented.
|
|
|
|
The driver has two adaptive modes (setting 1 or 3) in which
|
|
it dynamically adjusts the InterruptThrottleRate value based on the traffic
|
|
that it receives. After determining the type of incoming traffic in the last
|
|
timeframe, it will adjust the InterruptThrottleRate to an appropriate value
|
|
for that traffic.
|
|
|
|
The algorithm classifies the incoming traffic every interval into
|
|
classes. Once the class is determined, the InterruptThrottleRate value is
|
|
adjusted to suit that traffic type the best. There are three classes defined:
|
|
"Bulk traffic", for large amounts of packets of normal size; "Low latency",
|
|
for small amounts of traffic and/or a significant percentage of small
|
|
packets; and "Lowest latency", for almost completely small packets or
|
|
minimal traffic.
|
|
|
|
In dynamic conservative mode, the InterruptThrottleRate value is set to 4000
|
|
for traffic that falls in class "Bulk traffic". If traffic falls in the "Low
|
|
latency" or "Lowest latency" class, the InterruptThrottleRate is increased
|
|
stepwise to 20000. This default mode is suitable for most applications.
|
|
|
|
For situations where low latency is vital such as cluster or
|
|
grid computing, the algorithm can reduce latency even more when
|
|
InterruptThrottleRate is set to mode 1. In this mode, which operates
|
|
the same as mode 3, the InterruptThrottleRate will be increased stepwise to
|
|
70000 for traffic in class "Lowest latency".
|
|
|
|
In simplified mode the interrupt rate is based on the ratio of TX and
|
|
RX traffic. If the bytes per second rate is approximately equal, the
|
|
interrupt rate will drop as low as 2000 interrupts per second. If the
|
|
traffic is mostly transmit or mostly receive, the interrupt rate could
|
|
be as high as 8000.
|
|
|
|
Setting InterruptThrottleRate to 0 turns off any interrupt moderation
|
|
and may improve small packet latency, but is generally not suitable
|
|
for bulk throughput traffic.
|
|
|
|
NOTE: InterruptThrottleRate takes precedence over the TxAbsIntDelay and
|
|
RxAbsIntDelay parameters. In other words, minimizing the receive
|
|
and/or transmit absolute delays does not force the controller to
|
|
generate more interrupts than what the Interrupt Throttle Rate
|
|
allows.
|
|
|
|
NOTE: When e1000e is loaded with default settings and multiple adapters
|
|
are in use simultaneously, the CPU utilization may increase non-
|
|
linearly. In order to limit the CPU utilization without impacting
|
|
the overall throughput, we recommend that you load the driver as
|
|
follows:
|
|
|
|
modprobe e1000e InterruptThrottleRate=3000,3000,3000
|
|
|
|
This sets the InterruptThrottleRate to 3000 interrupts/sec for
|
|
the first, second, and third instances of the driver. The range
|
|
of 2000 to 3000 interrupts per second works on a majority of
|
|
systems and is a good starting point, but the optimal value will
|
|
be platform-specific. If CPU utilization is not a concern, use
|
|
RX_POLLING (NAPI) and default driver settings.
|
|
|
|
RxIntDelay
|
|
----------
|
|
Valid Range: 0-65535 (0=off)
|
|
Default Value: 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.
|
|
|
|
CAUTION: 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 0.
|
|
|
|
RxAbsIntDelay
|
|
-------------
|
|
Valid Range: 0-65535 (0=off)
|
|
Default Value: 8
|
|
|
|
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.
|
|
|
|
TxIntDelay
|
|
----------
|
|
Valid Range: 0-65535 (0=off)
|
|
Default Value: 8
|
|
|
|
This value delays the generation of transmit interrupts in units of
|
|
1.024 microseconds. Transmit interrupt reduction can improve CPU
|
|
efficiency if properly tuned for specific network traffic. If the
|
|
system is reporting dropped transmits, this value may be set too high
|
|
causing the driver to run out of available transmit descriptors.
|
|
|
|
TxAbsIntDelay
|
|
-------------
|
|
Valid Range: 0-65535 (0=off)
|
|
Default Value: 32
|
|
|
|
This value, in units of 1.024 microseconds, limits the delay in which a
|
|
transmit interrupt is generated. Useful only if TxIntDelay is non-zero,
|
|
this value ensures that an interrupt is generated after the initial
|
|
packet is sent on the wire within the set amount of time. Proper tuning,
|
|
along with TxIntDelay, may improve traffic throughput in specific
|
|
network conditions.
|
|
|
|
Copybreak
|
|
---------
|
|
Valid Range: 0-xxxxxxx (0=off)
|
|
Default Value: 256
|
|
|
|
Driver copies all packets below or equaling this size to a fresh RX
|
|
buffer before handing it up the stack.
|
|
|
|
This parameter is different than other parameters, in that it is a
|
|
single (not 1,1,1 etc.) parameter applied to all driver instances and
|
|
it is also available during runtime at
|
|
/sys/module/e1000e/parameters/copybreak
|
|
|
|
SmartPowerDownEnable
|
|
--------------------
|
|
Valid Range: 0-1
|
|
Default Value: 0 (disabled)
|
|
|
|
Allows PHY to turn off in lower power states. The user can set this parameter
|
|
in supported chipsets.
|
|
|
|
KumeranLockLoss
|
|
---------------
|
|
Valid Range: 0-1
|
|
Default Value: 1 (enabled)
|
|
|
|
This workaround skips resetting the PHY at shutdown for the initial
|
|
silicon releases of ICH8 systems.
|
|
|
|
IntMode
|
|
-------
|
|
Valid Range: 0-2 (0=legacy, 1=MSI, 2=MSI-X)
|
|
Default Value: 2
|
|
|
|
Allows changing the interrupt mode at module load time, without requiring a
|
|
recompile. If the driver load fails to enable a specific interrupt mode, the
|
|
driver will try other interrupt modes, from least to most compatible. The
|
|
interrupt order is MSI-X, MSI, Legacy. If specifying MSI (IntMode=1)
|
|
interrupts, only MSI and Legacy will be attempted.
|
|
|
|
CrcStripping
|
|
------------
|
|
Valid Range: 0-1
|
|
Default Value: 1 (enabled)
|
|
|
|
Strip the CRC from received packets before sending up the network stack. If
|
|
you have a machine with a BMC enabled but cannot receive IPMI traffic after
|
|
loading or enabling the driver, try disabling this feature.
|
|
|
|
WriteProtectNVM
|
|
---------------
|
|
Valid Range: 0,1
|
|
Default Value: 1
|
|
|
|
If set to 1, configure the hardware to ignore all write/erase cycles to the
|
|
GbE region in the ICHx NVM (in order to prevent accidental corruption of the
|
|
NVM). This feature can be disabled by setting the parameter to 0 during initial
|
|
driver load.
|
|
NOTE: The machine must be power cycled (full off/on) when enabling NVM writes
|
|
via setting the parameter to zero. Once the NVM has been locked (via the
|
|
parameter at 1 when the driver loads) it cannot be unlocked except via power
|
|
cycle.
|
|
|
|
Additional Configurations
|
|
=========================
|
|
|
|
Jumbo Frames
|
|
------------
|
|
Jumbo Frames support is enabled by changing the MTU to a value larger than
|
|
the default of 1500. Use the ifconfig command to increase the MTU size.
|
|
For example:
|
|
|
|
ifconfig eth<x> mtu 9000 up
|
|
|
|
This setting is not saved across reboots.
|
|
|
|
Notes:
|
|
|
|
- The maximum MTU setting for Jumbo Frames is 9216. This value coincides
|
|
with the maximum Jumbo Frames size of 9234 bytes.
|
|
|
|
- Using Jumbo Frames at 10 or 100 Mbps is not supported and may result in
|
|
poor performance or loss of link.
|
|
|
|
- Some adapters limit Jumbo Frames sized packets to a maximum of
|
|
4096 bytes and some adapters do not support Jumbo Frames.
|
|
|
|
Ethtool
|
|
-------
|
|
The driver utilizes the ethtool interface for driver configuration and
|
|
diagnostics, as well as displaying statistical information. We
|
|
strongly recommend downloading the latest version of ethtool at:
|
|
|
|
http://ftp.kernel.org/pub/software/network/ethtool/
|
|
|
|
Speed and Duplex
|
|
----------------
|
|
Speed and Duplex are configured through the ethtool* utility. For
|
|
instructions, refer to the ethtool man page.
|
|
|
|
Enabling Wake on LAN* (WoL)
|
|
---------------------------
|
|
WoL is configured through the ethtool* utility. For instructions on
|
|
enabling WoL with ethtool, refer to the ethtool man page.
|
|
|
|
WoL will be enabled on the system during the next shut down or reboot.
|
|
For this driver version, in order to enable WoL, the e1000e driver must be
|
|
loaded when shutting down or rebooting the system.
|
|
|
|
In most cases Wake On LAN is only supported on port A for multiple port
|
|
adapters. To verify if a port supports Wake on Lan run ethtool eth<X>.
|
|
|
|
Support
|
|
=======
|
|
|
|
For general information, go to the Intel support website at:
|
|
|
|
www.intel.com/support/
|
|
|
|
or the Intel Wired Networking project hosted by Sourceforge at:
|
|
|
|
http://sourceforge.net/projects/e1000
|
|
|
|
If an issue is identified with the released source code on the supported
|
|
kernel with a supported adapter, email the specific information related
|
|
to the issue to e1000-devel@lists.sf.net
|