aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/networking/s2io.txt199
1 files changed, 152 insertions, 47 deletions
diff --git a/Documentation/networking/s2io.txt b/Documentation/networking/s2io.txt
index 6726b524ec45..bd528ffbeb4b 100644
--- a/Documentation/networking/s2io.txt
+++ b/Documentation/networking/s2io.txt
@@ -1,48 +1,153 @@
1S2IO Technologies XFrame 10 Gig adapter. 1Release notes for Neterion's (Formerly S2io) Xframe I/II PCI-X 10GbE driver.
2------------------------------------------- 2
3 3Contents
4I. Module loadable parameters. 4=======
5When loaded as a module, the driver provides a host of Module loadable 5- 1. Introduction
6parameters, so the device can be tuned as per the users needs. 6- 2. Identifying the adapter/interface
7A list of the Module params is given below. 7- 3. Features supported
8(i) ring_num: This can be used to program the number of 8- 4. Command line parameters
9 receive rings used in the driver. 9- 5. Performance suggestions
10(ii) ring_len: This defines the number of descriptors each ring 10- 6. Available Downloads
11 can have. There can be a maximum of 8 rings. 11
12(iii) frame_len: This is an array of size 8. Using this we can 12
13 set the maximum size of the received frame that can 131. Introduction:
14 be steered into the corrsponding receive ring. 14This Linux driver supports Neterion's Xframe I PCI-X 1.0 and
15(iv) fifo_num: This defines the number of Tx FIFOs thats used in 15Xframe II PCI-X 2.0 adapters. It supports several features
16 the driver. 16such as jumbo frames, MSI/MSI-X, checksum offloads, TSO, UFO and so on.
17(v) fifo_len: Each element defines the number of 17See below for complete list of features.
18 Tx descriptors that can be associated with each 18All features are supported for both IPv4 and IPv6.
19 corresponding FIFO. There are a maximum of 8 FIFOs. 19
20(vi) tx_prio: This is a bool, if module is loaded with a non-zero 202. Identifying the adapter/interface:
21 value for tx_prio multi FIFO scheme is activated. 21a. Insert the adapter(s) in your system.
22(vii) rx_prio: This is a bool, if module is loaded with a non-zero 22b. Build and load driver
23 value for tx_prio multi RING scheme is activated. 23# insmod s2io.ko
24(viii) latency_timer: The value given against this param will be 24c. View log messages
25 loaded into the latency timer register in PCI Config 25# dmesg | tail -40
26 space, else the register is left with its reset value. 26You will see messages similar to:
27 27eth3: Neterion Xframe I 10GbE adapter (rev 3), Version 2.0.9.1, Intr type INTA
28II. Performance tuning. 28eth4: Neterion Xframe II 10GbE adapter (rev 2), Version 2.0.9.1, Intr type INTA
29 By changing a few sysctl parameters. 29eth4: Device is on 64 bit 133MHz PCIX(M1) bus
30 Copy the following lines into a file and run the following command, 30
31 "sysctl -p <file_name>" 31The above messages identify the adapter type(Xframe I/II), adapter revision,
32### IPV4 specific settings 32driver version, interface name(eth3, eth4), Interrupt type(INTA, MSI, MSI-X).
33net.ipv4.tcp_timestamps = 0 # turns TCP timestamp support off, default 1, reduces CPU use 33In case of Xframe II, the PCI/PCI-X bus width and frequency are displayed
34net.ipv4.tcp_sack = 0 # turn SACK support off, default on 34as well.
35# on systems with a VERY fast bus -> memory interface this is the big gainer 35
36net.ipv4.tcp_rmem = 10000000 10000000 10000000 # sets min/default/max TCP read buffer, default 4096 87380 174760 36To associate an interface with a physical adapter use "ethtool -p <ethX>".
37net.ipv4.tcp_wmem = 10000000 10000000 10000000 # sets min/pressure/max TCP write buffer, default 4096 16384 131072 37The corresponding adapter's LED will blink multiple times.
38net.ipv4.tcp_mem = 10000000 10000000 10000000 # sets min/pressure/max TCP buffer space, default 31744 32256 32768 38
39 393. Features supported:
40### CORE settings (mostly for socket and UDP effect) 40a. Jumbo frames. Xframe I/II supports MTU upto 9600 bytes,
41net.core.rmem_max = 524287 # maximum receive socket buffer size, default 131071 41modifiable using ifconfig command.
42net.core.wmem_max = 524287 # maximum send socket buffer size, default 131071 42
43net.core.rmem_default = 524287 # default receive socket buffer size, default 65535 43b. Offloads. Supports checksum offload(TCP/UDP/IP) on transmit
44net.core.wmem_default = 524287 # default send socket buffer size, default 65535 44and receive, TSO.
45net.core.optmem_max = 524287 # maximum amount of option memory buffers, default 10240 45
46net.core.netdev_max_backlog = 300000 # number of unprocessed input packets before kernel starts dropping them, default 300 46c. Multi-buffer receive mode. Scattering of packet across multiple
47---End of performance tuning file--- 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
129on certain 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.
48 153