User Manual

Rev 2.1-1.0.6
Mellanox Technologies
131
• Enable the TCP selective acks option for better CPU utilization:
7.2.3 Preserving Your Performance Settings after a Reboot
To preserve your performance settings after a reboot, you need to add them to the file /etc/
sysctl.conf as follows:
<sysctl name1>=<value1>
<sysctl name2>=<value2>
<sysctl name3>=<value3>
<sysctl name4>=<value4>
For example, “Tuning the Network Adapter for Improved IPv4 Traffic Performance” on
page 130 lists the following setting to disable the TCP timestamps option:
In order to keep the TCP timestamps option disabled after a reboot, add the following line to
/etc/sysctl.conf:
7.2.4 Tuning Power Management
Check that the output CPU frequency for each core is equal to the maximum supported and that
all core frequencies are consistent.
• Check the maximum supported CPU frequency:
• Check that core frequencies are consistent:
• Check that the output frequencies are the same as the maximum supported.
If the CPU frequency is not at the maximum, check the BIOS settings according to tables in is section
“Recommended BIOS Settings” on page 127 to verify that power state is disabled.
• Check the current CPU frequency to check whether it is configured to max available
frequency:
sysctl -w net.ipv4.tcp_sack=1
sysctl -w net.ipv4.tcp_timestamps=0
net.ipv4.tcp_timestamps=0
#cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_max_freq
#cat /proc/cpuinfo | grep "cpu MHz"
#cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq