NC51xx PCIe 10 Gigabit Server Adapter Software and Configuration Guide

Installation and configuration 15
o
Range = 1500|4074|8014 bytes
• Flow Control. Specifies the type of flow control that is needed.
o Default = Enabled
o Range = Disabled; Enabled
• Tx TCP Checksum Offload. Offloads the task of computing the checksum for outgoing TCP or UDP
packets, thereby improving performance.
o Default = On
o Range = Off; On
• Rx TCP Checksum Offload. Offloads the task of computing the checksum for incoming TCP or UDP
packets, thereby improving performance.
o Default = On
o Range = Off; On
• Large Send Offload. Enables offloading of large TCP packets. Large send offload cannot be enabled
on a port that has IPMI enabled (if IPMI is supported for your adapter).
o Default = Enabled
o Range = Disabled; Enabled
• Number of Transmit Descriptors: Minimum/Maximum. Specifies the number of descriptors to allocate
per Transmit Control Block (TCB). This value directly affects the number of map registers allocated for
the adapter (the higher the number, the more map registers are allocated). Transmit Descriptors
determine how many resources are allocated to transmit packets.
o Default = 1024
o Range = 1024|2048
• Number of Receive Descriptors: Minimum/Maximum. In high network load situations, increasing
receive descriptors can increase performance. The tradeoff is that this also increases the amount of
system memory used by the driver. If too few receive descriptors are used, performance suffers. If too
many receive descriptors are used, the driver unnecessarily consumes memory resources. Receive
Descriptors determine how many resources are allocated to receive packets.
o Default = 8192
o Range = 1024|2048|4096|8192|16384
• Number of Receive Descriptors (Jumbo). Receive Descriptors determine how many resources are
allocated to receive packets. This property is only applicable if Max Frame Size is greater than
1500.
o Default = 4096
o Range = 1024|2048|4096|8192
Linux installation
The nx_nic-<version>.src.rpm driver is released in a source RPM format. The package is dependent on the
kernel source code. The following sections describe how to install the driver using Red Hat and SUSE
distributions.
For SUSE installations, you must install the kernel source code or set up the source tree on your Linux
system before installing the driver.