You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
312 lines
12 KiB
312 lines
12 KiB
Linux* Driver for Intel(R) Ethernet Network Connection |
|
====================================================== |
|
|
|
Intel Gigabit Linux driver. |
|
Copyright(c) 1999 - 2013 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. |
|
|
|
- Jumbo Frames cannot be configured on an 82579-based Network device, if |
|
MACSec is enabled on the system. |
|
|
|
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/ |
|
|
|
NOTE: When validating enable/disable tests on some parts (82578, for example) |
|
you need to add a few seconds between tests when working with 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
|
|
|