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 upto 9600 bytes,
41modifiable using ifconfig 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(upto 7%
53on certain platforms).
54
55e. NAPI. Compile-time option(CONFIG_S2IO_NAPI) for better Rx interrupt 
56moderation.
57
58f. Statistics. Comprehensive MAC-level and software statistics displayed
59using "ethtool -S" option.
60
61g. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings, 
62with multiple steering options.
63
644.  Command line parameters
65a. tx_fifo_num
66Number of transmit queues
67Valid range: 1-8
68Default: 1
69
70b. rx_ring_num
71Number of receive rings
72Valid range: 1-8
73Default: 1
74
75c. tx_fifo_len
76Size of each transmit queue
77Valid range: Total length of all queues should not exceed 8192
78Default: 4096
79
80d. rx_ring_sz 
81Size of each receive ring(in 4K blocks)
82Valid range: Limited by memory on system
83Default: 30 
84
85e. intr_type
86Specifies interrupt type. Possible values 1(INTA), 2(MSI), 3(MSI-X)
87Valid range: 1-3
88Default: 1 
89
905.  Performance suggestions
91General:
92a. Set MTU to maximum(9000 for switch setup, 9600 in back-to-back configuration)
93b. Set TCP windows size to optimal value. 
94For instance, for MTU=1500 a value of 210K has been observed to result in 
95good performance.
96# sysctl -w net.ipv4.tcp_rmem="210000 210000 210000"
97# sysctl -w net.ipv4.tcp_wmem="210000 210000 210000"
98For MTU=9000, TCP window size of 10 MB is recommended.
99# sysctl -w net.ipv4.tcp_rmem="10000000 10000000 10000000"
100# sysctl -w net.ipv4.tcp_wmem="10000000 10000000 10000000"
101
102Transmit performance:
103a. By default, the driver respects BIOS settings for PCI bus parameters. 
104However, you may want to experiment with PCI bus parameters 
105max-split-transactions(MOST) and MMRBC (use setpci command). 
106A MOST value of 2 has been found optimal for Opterons and 3 for Itanium.  
107It could be different for your hardware.  
108Set MMRBC to 4K**.
109
110For example you can set 
111For opteron
112#setpci -d 17d5:* 62=1d 
113For Itanium
114#setpci -d 17d5:* 62=3d 
115
116For detailed description of the PCI registers, please see Xframe User Guide.
117
118b. Ensure Transmit Checksum offload is enabled. Use ethtool to set/verify this 
119parameter.
120c. Turn on TSO(using "ethtool -K")
121# ethtool -K <ethX> tso on
122
123Receive performance:
124a. By default, the driver respects BIOS settings for PCI bus parameters. 
125However, you may want to set PCI latency timer to 248.
126#setpci -d 17d5:* LATENCY_TIMER=f8
127For detailed description of the PCI registers, please see Xframe User Guide.
128b. Use 2-buffer mode. This results in large performance boost on
129certain platforms(eg. SGI Altix, IBM xSeries).
130c. Ensure Receive Checksum offload is enabled. Use "ethtool -K ethX" command to 
131set/verify this option.
132d. Enable NAPI feature(in kernel configuration Device Drivers ---> Network 
133device support --->  Ethernet (10000 Mbit) ---> S2IO 10Gbe Xframe NIC) to 
134bring down CPU utilization.
135
136** For AMD opteron platforms with 8131 chipset, MMRBC=1 and MOST=1 are 
137recommended as safe parameters.
138For more information, please review the AMD8131 errata at
139http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26310.pdf
140
1416.  Available Downloads
142Neterion "s2io" driver in Red Hat and Suse 2.6-based distributions is kept up 
143to date, also the latest "s2io" code (including support for 2.4 kernels) is 
144available via "Support" link on the Neterion site:  http://www.neterion.com.
145
146For Xframe User Guide (Programming manual), visit ftp site ns1.s2io.com,
147user: linuxdocs password: HALdocs
148
1497. Support 
150For further support please contact either your 10GbE Xframe NIC vendor (IBM, 
151HP, SGI etc.) or click on the "Support" link on the Neterion site:  
152http://www.neterion.com.
153