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.)
142