SGI® 10-Gigabit Ethernet Network Adapter User’s Guide

SGI ProPack Performance Tuning

This section discusses the following:

"Socket Read and Write Buffer Sizes for SGI ProPack" on page 19

"Jumbo Frames and SGI ProPack" on page 19

"Read/Write Size and SGI ProPack" on page 19

"TCP/IP Socket Buffer Size and SGI ProPack" on page 19

Socket Read and Write Buffer Sizes for SGI ProPack

The largest-allowed socket read and write buffer sizes are controlled by the following files:

Read: /proc/sys/net/core/rmem_max

Write: /proc/sys/net/core/wmem_max

Jumbo Frames and SGI ProPack

Using a large maximum transmission unit (MTU) is necessary for the best 10–Gbit Ethernet performance. Generally, the bigger the MTU, the better. The driver supports MTUs as large as 9600 bytes.

Read/Write Size and SGI ProPack

Applications should read large buffers from and write large buffers to the network for the best throughput and to reduce CPU utilization.

For example, an application that uses recv(2) calls with 32–KB buffers will generally have better throughput than if the application were to use twice as many recv calls with 16-KB buffers.

TCP/IP Socket Buffer Size and SGI ProPack

In SGI ProPack, /proc/sys/net/core/rmem_max and /proc/sys/net/core/wmem_max are both set to at least 524288 bytes, which is usually large enough to provide good performance. Reducing rmem_max and

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Silicon Power Computer & comm 74669003 SGI ProPack Performance Tuning, Socket Read and Write Buffer Sizes for SGI ProPack