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 thefollowing
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 buffersfrom 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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