NC51xx PCIe 10 Gigabit Server Adapter Software and Configuration Guide

Linux Socket Acceleration 26
• LSA does not support jumbo frames in this release. If the Maximum Transmission Unit (MTU) is set to
jumbo, LSA will default back to a 1500 byte payload.
• Newer versions of the Linux kernel will contain the netxen_nic driver, which supports the same
devices as nx_nic except without the LSA interface. The netxen_nic driver must be manually removed
and then the nx_nic driver must be installed prior to installing the nx_lsa driver. The following
command sequence can be used to remove the netxen_nic driver.
# rmmod netxen_nic
# rm /lib/modules/<kernel version>/kernel/drivers/net/netxen_nic.ko
Running LSA
After the appropriate rule is entered into nxoffload, no further user intervention is required and the offload
occurs automatically.
LSA statistics
LSA offloaded statistics can be viewed at the following location:
/proc/net/nx_nic/lsa_x/stats
Where: x defines the port number
The following output is an example of the collected statistics:
% cat /proc/net/nx_nic/lsa_1/stats
TCP/IP Statistics Port0 Port1 Port2 Port3
TcpMaxConn 0 0 0 0
TcpActiveOpens 20 0 0 0
TcpPassiveOpens 0 0 0 0
TcpAttemptFails 0 0 0 0
TcpEstabResets 0 0 0 0
TcpCurrEstab 12 0 0 0
TcpInSegs 10094835 0 0 0
TcpSlowOutSegs 131 0 0 0
TcpRetransSegs 33 0 0 0
TcpInErrs 0 0 0 0
TcpOutRsts 0 0 0 0
TcpOutCollapsed 0 0 0 0
The following list identifies and defines each statistic:
• TcpMaxConn: The limit on the total number of TCP connections that the entity can support. In entities
where the maximum number of connections is dynamic, this object should contain the value -1.
STATUS—Not supported
• TcpActiveOpens: The number of times TCP connections have made a direct transition from the
CLOSED state to the SYN-SENT state.
STATUS—Supported
• TcpPassiveOpens: The number of times TCP connections have made a direct transition from the
LISTEN state to the SYN-RCVD state.