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| -rw-r--r-- | Documentation/networking/e1000e.txt | 426 |
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diff --git a/Documentation/networking/e1000e.txt b/Documentation/networking/e1000e.txt index 12089547baed..33554e5416c5 100644 --- a/Documentation/networking/e1000e.txt +++ b/Documentation/networking/e1000e.txt @@ -1,8 +1,10 @@ +.. SPDX-License-Identifier: GPL-2.0+ + Linux* Driver for Intel(R) Ethernet Network Connection ====================================================== Intel Gigabit Linux driver. -Copyright(c) 1999 - 2013 Intel Corporation. +Copyright(c) 2008-2018 Intel Corporation. Contents ======== @@ -12,48 +14,43 @@ Contents - Additional Configurations - Support + Identifying Your Adapter ======================== +For information on how to identify your adapter, and for the latest Intel +network drivers, refer to the Intel Support website: +https://www.intel.com/support -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 +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:: -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: + modprobe e1000e [<option>=<VAL1>,<VAL2>,...] - http://support.intel.com/support/go/network/adapter/home.htm +There needs to be a <VAL#> for each network port in the system supported by +this driver. The values will be applied to each instance, in function order. +For example:: -Command Line Parameters -======================= + modprobe e1000e InterruptThrottleRate=16000,16000 +In this case, there are two network ports supported by e1000e in the system. 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 +NOTE: A descriptor describes a data buffer and attributes related to the data +buffer. This information is accessed by the hardware. InterruptThrottleRate --------------------- -Valid Range: 0,1,3,4,100-100000 (0=off, 1=dynamic, 3=dynamic conservative, - 4=simplified balancing) -Default Value: 3 +:Valid Range: 0,1,3,4,100-100000 +: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. +Interrupt Throttle Rate controls the number of interrupts each interrupt +vector can generate per second. Increasing ITR lowers latency at the cost of +increased CPU utilization, though it may help throughput in some circumstances. Setting InterruptThrottleRate to a value greater or equal to 100 will program the adapter to send out a maximum of that many interrupts @@ -81,232 +78,305 @@ 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. + - 0: Off + Turns off any interrupt moderation and may improve small packet latency. + However, this is generally not suitable for bulk throughput traffic due + to the increased CPU utilization of the higher interrupt rate. + - 1: Dynamic mode + This mode attempts to moderate interrupts per vector while maintaining + very low latency. This can sometimes cause extra CPU utilization. If + planning on deploying e1000e in a latency sensitive environment, this + parameter should be considered. + - 3: Dynamic Conservative mode (default) + 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. + - 4: Simplified Balancing mode + 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. + - 100-100000: + Setting InterruptThrottleRate to a value greater or equal to 100 + will program the adapter to send at most 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. + +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. RxIntDelay ---------- -Valid Range: 0-65535 (0=off) -Default Value: 0 +: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. +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 +: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. +receive interrupt is generated. This value ensures that an interrupt is +generated after the initial packet is received within the set amount of time, +which is useful only if RxIntDelay is non-zero. Proper tuning, along with +RxIntDelay, may improve traffic throughput in specific network conditions. TxIntDelay ---------- -Valid Range: 0-65535 (0=off) -Default Value: 8 +: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. +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 +: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. +transmit interrupt is generated. It is useful only if TxIntDelay is non-zero. +It 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 +copybreak --------- -Valid Range: 0-xxxxxxx (0=off) -Default Value: 256 +:Valid Range: 0-xxxxxxx (0=off) +:Default Value: 256 -Driver copies all packets below or equaling this size to a fresh RX +The driver copies all packets below or equaling this size to a fresh receive buffer before handing it up the stack. +This parameter differs from other parameters because 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. + +To use copybreak, type:: -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 + modprobe e1000e.ko copybreak=128 SmartPowerDownEnable -------------------- -Valid Range: 0-1 -Default Value: 0 (disabled) +: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. +Allows the 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) +:Valid Range: 0,1 +:Default Value: 1 (enabled) -This workaround skips resetting the PHY at shutdown for the initial -silicon releases of ICH8 systems. +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 +:Valid Range: 0-2 +:Default Value: 0 -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. + +-------+----------------+ + | Value | Interrupt Mode | + +=======+================+ + | 0 | Legacy | + +-------+----------------+ + | 1 | MSI | + +-------+----------------+ + | 2 | MSI-X | + +-------+----------------+ + +IntMode allows load time control over the type of interrupt registered for by +the driver. MSI-X is required for multiple queue support, and some kernels and +combinations of kernel .config options will force a lower level of interrupt +support. + +This command will show different values for each type of interrupt:: + + cat /proc/interrupts CrcStripping ------------ -Valid Range: 0-1 -Default Value: 1 (enabled) +:Valid Range: 0,1 +:Default Value: 1 (enabled) -Strip the CRC from received packets before sending up the network stack. If +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 +:Valid Range: 0,1 +:Default Value: 1 (enabled) 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 -========================= +Debug +----- +:Valid Range: 0-16 (0=none,...,16=all) +:Default Value: 0 - 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: +This parameter adjusts the level of debug messages displayed in the system logs. + + +Additional Features and Configurations +====================================== + +Jumbo Frames +------------ +Jumbo Frames support is enabled by changing the Maximum Transmission Unit (MTU) +to a value larger than the default value of 1500. - ifconfig eth<x> mtu 9000 up +Use the ifconfig command to increase the MTU size. For example, enter the +following where <x> is the interface number:: - This setting is not saved across reboots. + ifconfig eth<x> mtu 9000 up - Notes: +Alternatively, you can use the ip command as follows:: - - The maximum MTU setting for Jumbo Frames is 9216. This value coincides - with the maximum Jumbo Frames size of 9234 bytes. + ip link set mtu 9000 dev eth<x> + ip link set up dev eth<x> - - Using Jumbo frames at 10 or 100 Mbps is not supported and may result in - poor performance or loss of link. +This setting is not saved across reboots. The setting change can be made +permanent by adding 'MTU=9000' to the file: - - Some adapters limit Jumbo Frames sized packets to a maximum of - 4096 bytes and some adapters do not support Jumbo Frames. +- For RHEL: /etc/sysconfig/network-scripts/ifcfg-eth<x> +- For SLES: /etc/sysconfig/network/<config_file> - - Jumbo Frames cannot be configured on an 82579-based Network device, if - MACSec is enabled on the system. +NOTE: The maximum MTU setting for Jumbo Frames is 8996. This value coincides +with the maximum Jumbo Frames size of 9018 bytes. - 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: +NOTE: Using Jumbo frames at 10 or 100 Mbps is not supported and may result in +poor performance or loss of link. - https://kernel.org/pub/software/network/ethtool/ +NOTE: The following adapters limit Jumbo Frames sized packets to a maximum of +4088 bytes: - 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. + - Intel(R) 82578DM Gigabit Network Connection + - Intel(R) 82577LM Gigabit Network Connection - Speed and Duplex - ---------------- - Speed and Duplex are configured through the ethtool* utility. For - instructions, refer to the ethtool man page. +The following adapters do not support Jumbo Frames: - 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. + - Intel(R) PRO/1000 Gigabit Server Adapter + - Intel(R) PRO/1000 PM Network Connection + - Intel(R) 82562G 10/100 Network Connection + - Intel(R) 82562G-2 10/100 Network Connection + - Intel(R) 82562GT 10/100 Network Connection + - Intel(R) 82562GT-2 10/100 Network Connection + - Intel(R) 82562V 10/100 Network Connection + - Intel(R) 82562V-2 10/100 Network Connection + - Intel(R) 82566DC Gigabit Network Connection + - Intel(R) 82566DC-2 Gigabit Network Connection + - Intel(R) 82566DM Gigabit Network Connection + - Intel(R) 82566MC Gigabit Network Connection + - Intel(R) 82566MM Gigabit Network Connection + - Intel(R) 82567V-3 Gigabit Network Connection + - Intel(R) 82577LC Gigabit Network Connection + - Intel(R) 82578DC Gigabit Network Connection - 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. +NOTE: 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. The latest ethtool +version is required for this functionality. Download it at: + +https://www.kernel.org/pub/software/network/ethtool/ + +NOTE: When validating enable/disable tests on some parts (for example, 82578), +it is necessary to add a few seconds between tests when working with ethtool. + + +Speed and Duplex Configuration +------------------------------ +In addressing speed and duplex configuration issues, you need to distinguish +between copper-based adapters and fiber-based adapters. + +In the default mode, an Intel(R) Ethernet Network Adapter using copper +connections will attempt to auto-negotiate with its link partner to determine +the best setting. If the adapter cannot establish link with the link partner +using auto-negotiation, you may need to manually configure the adapter and link +partner to identical settings to establish link and pass packets. This should +only be needed when attempting to link with an older switch that does not +support auto-negotiation or one that has been forced to a specific speed or +duplex mode. Your link partner must match the setting you choose. 1 Gbps speeds +and higher cannot be forced. Use the autonegotiation advertising setting to +manually set devices for 1 Gbps and higher. + +Speed, duplex, and autonegotiation advertising are configured through the +ethtool* utility. + +Caution: Only experienced network administrators should force speed and duplex +or change autonegotiation advertising manually. The settings at the switch must +always match the adapter settings. Adapter performance may suffer or your +adapter may not operate if you configure the adapter differently from your +switch. + +An Intel(R) Ethernet Network Adapter using fiber-based connections, however, +will not attempt to auto-negotiate with its link partner since those adapters +operate only in full duplex and only at their native speed. + + +Enabling Wake on LAN* (WoL) +--------------------------- +WoL is configured through the ethtool* utility. + +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 +prior to shutting down or suspending the system. + +NOTE: Wake on LAN is only supported on port A for the following devices: +- Intel(R) PRO/1000 PT Dual Port Network Connection +- Intel(R) PRO/1000 PT Dual Port Server Connection +- Intel(R) PRO/1000 PT Dual Port Server Adapter +- Intel(R) PRO/1000 PF Dual Port Server Adapter +- Intel(R) PRO/1000 PT Quad Port Server Adapter +- Intel(R) Gigabit PT Quad Port Server ExpressModule - 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/ +https://www.intel.com/support/ or the Intel Wired Networking project hosted by Sourceforge at: - http://sourceforge.net/projects/e1000 +https://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 +If an issue is identified with the released source code on a supported kernel +with a supported adapter, email the specific information related to the issue +to e1000-devel@lists.sf.net. |