1Release notes for Neterion's (Formerly S2io) Xframe I/II PCI-X 10GbE driver.
  2
  3Contents
  4=======
  5- 1.  Introduction
  6- 2.  Identifying the adapter/interface
  7- 3.  Features supported
  8- 4.  Command line parameters
  9- 5.  Performance suggestions
 10- 6.  Available Downloads 
 11
 12
 131.	Introduction:
 14This Linux driver supports Neterion's Xframe I PCI-X 1.0 and
 15Xframe II PCI-X 2.0 adapters. It supports several features 
 16such as jumbo frames, MSI/MSI-X, checksum offloads, TSO, UFO and so on.
 17See below for complete list of features.
 18All features are supported for both IPv4 and IPv6.
 19
 202.	Identifying the adapter/interface:
 21a. Insert the adapter(s) in your system.
 22b. Build and load driver 
 23# insmod s2io.ko
 24c. View log messages
 25# dmesg | tail -40
 26You will see messages similar to:
 27eth3: Neterion Xframe I 10GbE adapter (rev 3), Version 2.0.9.1, Intr type INTA
 28eth4: Neterion Xframe II 10GbE adapter (rev 2), Version 2.0.9.1, Intr type INTA
 29eth4: Device is on 64 bit 133MHz PCIX(M1) bus
 30
 31The above messages identify the adapter type(Xframe I/II), adapter revision,
 32driver version, interface name(eth3, eth4), Interrupt type(INTA, MSI, MSI-X).
 33In case of Xframe II, the PCI/PCI-X bus width and frequency are displayed
 34as well.
 35
 36To associate an interface with a physical adapter use "ethtool -p <ethX>".
 37The corresponding adapter's LED will blink multiple times.
 38
 393.	Features supported:
 40a. Jumbo frames. Xframe I/II supports MTU up to 9600 bytes,
 41modifiable using ip command.
 42
 43b. Offloads. Supports checksum offload(TCP/UDP/IP) on transmit
 44and receive, TSO.
 45
 46c. Multi-buffer receive mode. Scattering of packet across multiple
 47buffers. Currently driver supports 2-buffer mode which yields
 48significant performance improvement on certain platforms(SGI Altix,
 49IBM xSeries).
 50
 51d. MSI/MSI-X. Can be enabled on platforms which support this feature
 52(IA64, Xeon) resulting in noticeable performance improvement(up to 7%
 53on certain platforms).
 54
 55e. Statistics. Comprehensive MAC-level and software statistics displayed
 56using "ethtool -S" option.
 57
 58f. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings,
 59with multiple steering options.
 60
 614.  Command line parameters
 62a. tx_fifo_num
 63Number of transmit queues
 64Valid range: 1-8
 65Default: 1
 66
 67b. rx_ring_num
 68Number of receive rings
 69Valid range: 1-8
 70Default: 1
 71
 72c. tx_fifo_len
 73Size of each transmit queue
 74Valid range: Total length of all queues should not exceed 8192
 75Default: 4096
 76
 77d. rx_ring_sz 
 78Size of each receive ring(in 4K blocks)
 79Valid range: Limited by memory on system
 80Default: 30 
 81
 82e. intr_type
 83Specifies interrupt type. Possible values 0(INTA), 2(MSI-X)
 84Valid values: 0, 2
 85Default: 2
 86
 875.  Performance suggestions
 88General:
 89a. Set MTU to maximum(9000 for switch setup, 9600 in back-to-back configuration)
 90b. Set TCP windows size to optimal value. 
 91For instance, for MTU=1500 a value of 210K has been observed to result in 
 92good performance.
 93# sysctl -w net.ipv4.tcp_rmem="210000 210000 210000"
 94# sysctl -w net.ipv4.tcp_wmem="210000 210000 210000"
 95For MTU=9000, TCP window size of 10 MB is recommended.
 96# sysctl -w net.ipv4.tcp_rmem="10000000 10000000 10000000"
 97# sysctl -w net.ipv4.tcp_wmem="10000000 10000000 10000000"
 98
 99Transmit performance:
100a. By default, the driver respects BIOS settings for PCI bus parameters. 
101However, you may want to experiment with PCI bus parameters 
102max-split-transactions(MOST) and MMRBC (use setpci command). 
103A MOST value of 2 has been found optimal for Opterons and 3 for Itanium.  
104It could be different for your hardware.  
105Set MMRBC to 4K**.
106
107For example you can set 
108For opteron
109#setpci -d 17d5:* 62=1d 
110For Itanium
111#setpci -d 17d5:* 62=3d 
112
113For detailed description of the PCI registers, please see Xframe User Guide.
114
115b. Ensure Transmit Checksum offload is enabled. Use ethtool to set/verify this 
116parameter.
117c. Turn on TSO(using "ethtool -K")
118# ethtool -K <ethX> tso on
119
120Receive performance:
121a. By default, the driver respects BIOS settings for PCI bus parameters. 
122However, you may want to set PCI latency timer to 248.
123#setpci -d 17d5:* LATENCY_TIMER=f8
124For detailed description of the PCI registers, please see Xframe User Guide.
125b. Use 2-buffer mode. This results in large performance boost on
126certain platforms(eg. SGI Altix, IBM xSeries).
127c. Ensure Receive Checksum offload is enabled. Use "ethtool -K ethX" command to 
128set/verify this option.
129d. Enable NAPI feature(in kernel configuration Device Drivers ---> Network 
130device support --->  Ethernet (10000 Mbit) ---> S2IO 10Gbe Xframe NIC) to 
131bring down CPU utilization.
132
133** For AMD opteron platforms with 8131 chipset, MMRBC=1 and MOST=1 are 
134recommended as safe parameters.
135For more information, please review the AMD8131 errata at
136http://vip.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/
13726310_AMD-8131_HyperTransport_PCI-X_Tunnel_Revision_Guide_rev_3_18.pdf
138
1396. Support
140For further support please contact either your 10GbE Xframe NIC vendor (IBM, 
141HP, SGI etc.)