IBM PRO/100 SP manual Coalesce Buffers, Link Speed & Duplex, Locally Administered Address LAA

Although this is the safest setting, the best performance is achieved when the threshold parameter is as low as possible without producing underruns. To experiment, set the parameter to 16. Then, if performance drops significantly, increase the value in small increments.

Coalesce Buffers

The rcommended value is 8 with a range of 1–32. This specifies the number of memory buffers available to the driver in case the driver runs out of available Map Registers. This buffer area is also used when a packet consists of many fragments. If no coalesce buffers or map registers are available, the driver will be forced to queue the packet for later transmission. The most effective method of transmitting data, however, is to use map registers.

Link Speed & Duplex

The recommended setting is Auto Detect (default). This parameter lets the adapter know what speed to use on the Ethernet wire, and how to send and receive packets, either full or half duplex. The following options are available:

vAuto Detect

The adapter detects whether its environment can support a speed of 100Mbps, and uses that speed if possible. It also negotiates with the switch on whether to send and receive packets at full or half duplex.

v10Mbps/Half Duplex

The adapter uses a speed of 10Mbps and performs one operation at a time. It either sends or receives.

v10Mbps/Full Duplex

The adapter uses a speed of 10Mbps and sends and receives packets at the same time. This improves the performance of your adapter. Select this mode only if you have a full-duplex switch.

Locally Administered Address (LAA)

You can optionally override the factory default network address of the adapter. To enter a new network address, type a 12-digit hexadecimal number in this box. The address entered should be in the range of

000000000000—FFFFFFFFFFFF. Exceptions: Do not use a multicast address (LSB of the high byte = 1). For example, in the address 0X123456789AB, X cannot be an odd number. A value of 000000000000 will default to the address set at the factory.

PCI Bus Efficiency

When enabled, this option causes all transmit packets to be coalesced into a single buffer before being sent to the network card. Because the entire frame

1-10Intel® PRO/100 SP Mobile Combo Adapter: User’s Guide