e1000e(1)							     e1000e(1)



NAME
       e1000e -This file describes the Linux* Base Driver for the Gigabit Fam-
       ily of Adapters.


SYNOPSIS
       modprobe e1000e [<option>=<VAL1>,<VAL2>,...]


DESCRIPTION
       This driver is intended for  2.4.x  and	2.6.x  kernels.	  This	driver
       includes support for Intel(R) 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 adapter.  All hard-
       ware requirements listed apply to use with Linux.



OPTIONS
       The following optional parameters are used by entering them on the com-
       mand line with the modprobe command.


       InterruptThrottleRate

	      Valid Range: 0,1,3,100-100000 (0=off, 1=dynamic, 3=dynamic  con-
	      servative)

	      Default Value: 3

	      This  represents the maximum number of interrupts per second the
	      controller generates.  InterruptThrottleRate is another  setting
	      used  in	interrupt  moderation.	 Dynamic mode uses a heuristic
	      algorithm to adjust InterruptThrottleRate based on  the  current
	      traffic load.

	      The  default  setting  is	 configured to optimize interrupts for
	      bulk throughput while keeping CPU utilization low.  However this
	      setting  may result in slower overall transfer speeds if network
	      traffic consists mostly of small packets.	 If this is the	 case,
	      change this value to 0.

	      NOTE:  InterruptThrottleRate takes precedence over the TxAbsInt-
	      Delay 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.

	      See the section "InterruptThrottleRate" in Readme.


       RxIntDelay

	      Valid Range: 0-65535 (0=off)
	      Default Value: 0

	      This  sets the delay of 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 traf-
	      fic.  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 con-
	      ditions.	If this occurs a NETDEV WATCHDOG message is logged  in
	      the  system event log.  In addition, the controller is automati-
	      cally reset, restoring the network connection.  To eliminate the
	      potential for the hang ensure that RxIntDelay is set to zero.


       RxAbsIntDelay

	      Valid Range: 0-65535 (0=off)
	      Default Value: 128

	      This  limits the delay in which a receive interrupt is generated
	      (in units of 1.024 microseconds).	 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: 64

	      This sets the delay of 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: 64

	      This limits the delay in which a transmit interrupt is generated
	      (in units of 1.024 microseconds).	 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

	      Usage: insmod e1000e.ko copybreak=128

	      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/mod-
	      ule/e1000e/parameters/copybreak


       SmartPowerDownEnable

	      Valid Range: 0-1
	      Default Value: 1 (uses EEPROM settings); 0 (disabled for 82571EB
	      and 82572-based network connections)

	      Allows  Phy to turn off in lower power states. The user can turn
	      off this parameter in supported chipsets.


       KumeranLockLoss

	      Valid Range: 0-1
	      Default Value: 1 (enabled)

	      This workaround skips resetting the Phy at shutdown for the ini-
	      tial silicon releases of ICH8 systems.


       IntMode

	      Valid Range: 0-2 (0=legacy, 1=MSI, 2=MSI-X)
	      Default Value: 1 (MSI)

	      Allows  changing the interrupt mode at module load time, without
	      requiring a recompile. If the driver load fails to enable a spe-
	      cific 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.



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 ethx mtu 9000 up

       NOTE: Jumbo Frames are supported at 1000 Mbps only.  Using Jumbo Frames
       at 10 or 100 Mbps may result in poor performance or loss of link.

       The maximum MTU setting for Jumbo Frames is 9216.  This value coincides
       with the maximum Jumbo Frames size of 9234 bytes.

       Adapters based on the Intel(R)  82573V/E	 controllers  do  not  support
       Jumbo Frames.

       See the section "Jumbo Frames" in Readme.




Ethtool
       The  driver utilizes the ethtool interface for driver configuration and
       diagnostics, as well as displaying  statistical	information.   Ethtool
       version	3  or  later  is  required for this functionality, although we
       strongly recommend downloading the latest  version  at:	http://source-
       forge.net/projects/gkernel.



SPEED AND DUPLEX SETTINGS
       Speed  and Duplex are configured through the Ethtool* utility.  Ethtool
       is included with all versions of Red Hat after Red Hat7.2.   For	 other
       Linux  distributions,  download	and install Ethtool from the following
       website: http://sourceforge.net/projects/gkernel.



NAPI
       NAPI (Rx polling mode) is supported in  the  e1000e  driver.   NAPI  is
       enabled by default.

       To  disable NAPI, compile the driver module, passing in a configuration
       option:

	      make CFLAGS_EXTRA=-DE1000E_NO_NAPI install

       See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI.



SUPPORT
       For additional information, including supported adapters, building, and
       installation, see the Readme file included with the driver.

       For general information, go to the Intel support website at:

	      http://support.intel.com




				 May 29, 2008			     e1000e(1)