
Issue 11
© Solarflare Communications 2014
96
Solarflare Server Adapter
User Guide
Tuning Recommendations
The following tables provide recommendations for tuning settings for different applications.
Throughput -
Latency -
Forwarding -
Recommended Throughput Tuning
Table 22: Throughput Tuning Settings
Tuning Parameter
How?
MTU Size to maximum
supported by network
/sbin/ifconfig <ethX> mtu <size>
Interrupt moderation
Leave at default
TCP/IP Checksum Offload
Leave at default
TCP Segmentation Offload
Leave at default
TCP Large Receive Offload
Leave at default
TCP Protocol Tuning
Leave at default for 2.6.16 and later kernels.
For earlier kernels:
sysctl net.core.tcp_rmem 4096 87380 524288
sysctl net.core.tcp_wmem 4096 87380 524288
Receive Side Scaling (RSS)
Application dependent
Interrupt affinity & irqbalance
service
Interrupt affinity application dependent
Stop irq balance service:
/sbin/service irqbalance stop
Reload the drivers to use the driver default interrupt
affinity.
Buffer Allocation Method
Leave at default. Some applications may benefit from
specific setting.
The Solarflare driver now supports a single optimized
buffer allocation strategy and any value set by the
rx_alloc_method parameter is ignored.
PCI Express Lane Configuration
Ensure current speed (not the supported speed) reads
back as “x8 and 5Gb/s” Or “x8 and Unknown”
CPU Speed Service (cpuspeed)
Leave enabled