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Based on kernel version 3.13. Page generated on 2014-01-20 22:04 EST.

1	Release notes for Neterion's (Formerly S2io) Xframe I/II PCI-X 10GbE driver.
2	
3	Contents
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	
13	1.	Introduction:
14	This Linux driver supports Neterion's Xframe I PCI-X 1.0 and
15	Xframe II PCI-X 2.0 adapters. It supports several features 
16	such as jumbo frames, MSI/MSI-X, checksum offloads, TSO, UFO and so on.
17	See below for complete list of features.
18	All features are supported for both IPv4 and IPv6.
19	
20	2.	Identifying the adapter/interface:
21	a. Insert the adapter(s) in your system.
22	b. Build and load driver 
23	# insmod s2io.ko
24	c. View log messages
25	# dmesg | tail -40
26	You will see messages similar to:
27	eth3: Neterion Xframe I 10GbE adapter (rev 3), Version 2.0.9.1, Intr type INTA
28	eth4: Neterion Xframe II 10GbE adapter (rev 2), Version 2.0.9.1, Intr type INTA
29	eth4: Device is on 64 bit 133MHz PCIX(M1) bus
30	
31	The above messages identify the adapter type(Xframe I/II), adapter revision,
32	driver version, interface name(eth3, eth4), Interrupt type(INTA, MSI, MSI-X).
33	In case of Xframe II, the PCI/PCI-X bus width and frequency are displayed
34	as well.
35	
36	To associate an interface with a physical adapter use "ethtool -p <ethX>".
37	The corresponding adapter's LED will blink multiple times.
38	
39	3.	Features supported:
40	a. Jumbo frames. Xframe I/II supports MTU up to 9600 bytes,
41	modifiable using ifconfig command.
42	
43	b. Offloads. Supports checksum offload(TCP/UDP/IP) on transmit
44	and receive, TSO.
45	
46	c. Multi-buffer receive mode. Scattering of packet across multiple
47	buffers. Currently driver supports 2-buffer mode which yields
48	significant performance improvement on certain platforms(SGI Altix,
49	IBM xSeries).
50	
51	d. MSI/MSI-X. Can be enabled on platforms which support this feature
52	(IA64, Xeon) resulting in noticeable performance improvement(up to 7%
53	on certain platforms).
54	
55	e. Statistics. Comprehensive MAC-level and software statistics displayed
56	using "ethtool -S" option.
57	
58	f. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings,
59	with multiple steering options.
60	
61	4.  Command line parameters
62	a. tx_fifo_num
63	Number of transmit queues
64	Valid range: 1-8
65	Default: 1
66	
67	b. rx_ring_num
68	Number of receive rings
69	Valid range: 1-8
70	Default: 1
71	
72	c. tx_fifo_len
73	Size of each transmit queue
74	Valid range: Total length of all queues should not exceed 8192
75	Default: 4096
76	
77	d. rx_ring_sz 
78	Size of each receive ring(in 4K blocks)
79	Valid range: Limited by memory on system
80	Default: 30 
81	
82	e. intr_type
83	Specifies interrupt type. Possible values 0(INTA), 2(MSI-X)
84	Valid values: 0, 2
85	Default: 2
86	
87	5.  Performance suggestions
88	General:
89	a. Set MTU to maximum(9000 for switch setup, 9600 in back-to-back configuration)
90	b. Set TCP windows size to optimal value. 
91	For instance, for MTU=1500 a value of 210K has been observed to result in 
92	good performance.
93	# sysctl -w net.ipv4.tcp_rmem="210000 210000 210000"
94	# sysctl -w net.ipv4.tcp_wmem="210000 210000 210000"
95	For 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	
99	Transmit performance:
100	a. By default, the driver respects BIOS settings for PCI bus parameters. 
101	However, you may want to experiment with PCI bus parameters 
102	max-split-transactions(MOST) and MMRBC (use setpci command). 
103	A MOST value of 2 has been found optimal for Opterons and 3 for Itanium.  
104	It could be different for your hardware.  
105	Set MMRBC to 4K**.
106	
107	For example you can set 
108	For opteron
109	#setpci -d 17d5:* 62=1d 
110	For Itanium
111	#setpci -d 17d5:* 62=3d 
112	
113	For detailed description of the PCI registers, please see Xframe User Guide.
114	
115	b. Ensure Transmit Checksum offload is enabled. Use ethtool to set/verify this 
116	parameter.
117	c. Turn on TSO(using "ethtool -K")
118	# ethtool -K <ethX> tso on
119	
120	Receive performance:
121	a. By default, the driver respects BIOS settings for PCI bus parameters. 
122	However, you may want to set PCI latency timer to 248.
123	#setpci -d 17d5:* LATENCY_TIMER=f8
124	For detailed description of the PCI registers, please see Xframe User Guide.
125	b. Use 2-buffer mode. This results in large performance boost on
126	certain platforms(eg. SGI Altix, IBM xSeries).
127	c. Ensure Receive Checksum offload is enabled. Use "ethtool -K ethX" command to 
128	set/verify this option.
129	d. Enable NAPI feature(in kernel configuration Device Drivers ---> Network 
130	device support --->  Ethernet (10000 Mbit) ---> S2IO 10Gbe Xframe NIC) to 
131	bring down CPU utilization.
132	
133	** For AMD opteron platforms with 8131 chipset, MMRBC=1 and MOST=1 are 
134	recommended as safe parameters.
135	For more information, please review the AMD8131 errata at
136	http://vip.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/
137	26310_AMD-8131_HyperTransport_PCI-X_Tunnel_Revision_Guide_rev_3_18.pdf
138	
139	6. Support
140	For further support please contact either your 10GbE Xframe NIC vendor (IBM, 
141	HP, SGI etc.)
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