readme

linux系统的网卡驱动包

Linux* Base Driver for Intel(R) Network Connection
===============================================================

November 25, 2007

Contents
========

- In This Release
- Identifying Your Adapter
- Building and Installation
- Command Line Parameters
- Speed and Duplex Configuration
- Additional Configurations
- Known Issues/Troubleshooting
- Support


In This Release
===============

This file describes the e1000 Linux* Base Driver for Intel Network Connection.  
This driver supports kernel versions 2.4.x and 2.6.x.  This driver includes 
support for Itanium(R)2-based systems.

This driver is only supported as a loadable module at this time.  Intel is
not supplying patches against the kernel source to allow for static linking
of the driver.  For questions related to hardware requirements, refer to the
documentation supplied with your Intel Gigabit adapter.  All hardware
requirements listed apply to use with Linux.

This release includes support for Intel(R) I/O Acceleration Technology,
Intel(R) I/OAT. You can find additional information on Intel I/OAT at 
http://www.intel.com/technology/ioacceleration/index.htm.

The following features are now available in supported kernels:
 - Native VLANs
 - Channel Bonding (teaming)
 - SNMP

Channel Bonding documentation can be found in the Linux kernel source:
/Documentation/networking/bonding.txt

The driver information previously displayed in the /proc filesystem is not
supported in this release.  Alternatively, you can use ethtool (version 1.6
or later), lspci, and ifconfig to obtain the same information.

Instructions on updating ethtool can be found in the section "Additional
Configurations" later in this document.

NOTE: The Intel(R) 82562v 10/100 Network Connection only provides 10/100
support.


Identifying Your Adapter
========================

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://downloadcenter.intel.com/scripts-df-external/Support_Intel.aspx


Building and Installation
=========================

To build a binary RPM* package of this driver, run 'rpmbuild -tb
<filename.tar.gz>'.  Replace <filename.tar.gz> with the specific filename
of the driver.

NOTE: For the build to work properly, the currently running kernel MUST
      match the version and configuration of the installed kernel sources.
      If you have just recompiled the kernel reboot the system now.

      RPM functionality has only been tested in Red Hat distributions.

1. Move the base driver tar file to the directory of your choice.  For
   example, use /home/username/e1000 or /usr/local/src/e1000.

2. Untar/unzip archive:

     tar zxf e1000-x.x.x.tar.gz

3. Change to the driver src directory:

     cd e1000-x.x.x/src/

4. Compile the driver module:

     make install

   The binary will be installed as:

     /lib/modules/<KERNEL VERSION>/kernel/drivers/net/e1000/e1000.[k]o

   The install locations listed above are the default locations.  They
   might not be correct for certain Linux distributions. 

5. Load the module using either the insmod or modprobe command:

     modprobe e1000

     insmod e1000

   Note that for 2.6 kernels the insmod command can be used if the full
   path to the driver module is specified.  For example:

     insmod /lib/modules/<KERNEL VERSION>/kernel/drivers/net/e1000/e1000.ko

   With 2.6 based kernels also make sure that older e1000 drivers are 
   removed from the kernel, before loading the new module:

     rmmod e1000; modprobe e1000


6. Assign an IP address to the interface by entering the following, where
   x is the interface number:

     ifconfig ethx <IP_address>

7. Verify that the interface works.  Enter the following, where <IP_address>
   is the IP address for another machine on the same subnet as the
   interface that is being tested:

     ping  <IP_address>	


Command Line Parameters
=======================

If the driver is built as a module, the  following optional parameters
are used by entering them on the command line with the modprobe command
using this syntax:

     modprobe e1000 [<option>=<VAL1>,<VAL2>,...]

For example, with two Gigabit PCI adapters, entering:

     modprobe e1000 TxDescriptors=80,128

loads the e1000 driver with 80 TX descriptors for the first adapter and
128 TX descriptors for the second adapter.

The default value for each parameter is generally the recommended setting,
unless otherwise noted.

NOTES:  For more information about the AutoNeg, Duplex, and Speed
        parameters, see the "Speed and Duplex Configuration" section in
        this document.

        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

        A descriptor describes a data buffer and attributes related to
        the data buffer.  This information is accessed by the hardware.


AutoNeg
-------
(Supported only on adapters with copper connections)
Valid Range:   0x01-0x0F, 0x20-0x2F
Default Value: 0x2F

This parameter is a bit-mask that specifies the speed and duplex settings
advertised by the adapter.  When this parameter is used, the Speed and
Duplex parameters must not be specified.

NOTE:  Refer to the Speed and Duplex section of this readme for more
       information on the AutoNeg parameter.


Duplex
------
(Supported only on adapters with copper connections)
Valid Range:   0-2 (0=auto-negotiate, 1=half, 2=full)
Default Value: 0

This defines the direction in which data is allowed to flow.  Can be
either one or two-directional.  If both Duplex and the link partner are
set to auto-negotiate, the board auto-detects the correct duplex.  If the
link partner is forced (either full or half), Duplex defaults to half-
duplex.


FlowControl
-----------
Valid Range:   0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx)
Default Value: Reads flow control settings from the EEPROM

This parameter controls the automatic generation(Tx) and response(Rx)
to Ethernet PAUSE frames.


InterruptThrottleRate
---------------------
(not supported on Intel(R) 82542, 82543 or 82544-based adapters)
Valid Range:   0,1,3,100-100000 (0=off, 1=dynamic, 3=dynamic conservative)
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.

Since 7.3.x, 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".

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.

CAUTION:  If you are using the Intel(R) PRO/1000 CT Network Connection
          (controller 82547), setting InterruptThrottleRate to a value
          greater than 75,000, may hang (stop transmitting) adapters
          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 InterruptThrottleRate is set no greater
          than 75,000 and is not set to 0.

NOTE:  When e1000 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 e1000 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.



RxDescriptors
-------------
Valid Range:   80-256 for 82542 and 82543-based adapters