Tuning CPUs and Hugepages on a Linux System

Introduction
This video will focus on CPU tuning and configuring hugepages on a Red Hat 8 system. We will be using tuna to view open CPU threads, filtering the output for a specific script, then isolating the script to a specific CPU. When CPU tuning is complete, you will set a value for hugepages and disable transparent hugepages, then confirm the changes after loading the new configuration.

Solution
Log in to the Red Hat 8 server using the credentials provided:

ssh cloud_user@PUBLIC_IP_ADDRESS
Note: When copying and pasting code into Vim, first enter :set paste (and then i to enter insert mode) to avoid adding unnecessary spaces and hashes. To save and quit the file, press Escape followed by :wq. To exit the file without saving, press Escape followed by :q!.

Manage CPU Affinity Using a PID or Process Name
Install the tuna package:
sudo yum install tuna -y

Launch the affinity.sh script in the background:
./scripts/affinity.sh &

Use tuna to show open threads, filtering for dd:
tuna -t dd -P
Use tuna to move the dd instance to CPU 0:
tuna -c 0 -t dd\* --move
Verify changes:
tuna -t dd -P
Kill the dd process:
sudo kill -9 PID_NUMBER
Manage CPU Affinity Using Systemd

Enable and start the evodd service:
sudo systemctl enable evodd --now

Check process affinity:
tuna -t dd -P
Use systecmctl to create an override file for the evodd service.
sudo systemctl edit evodd.service

Populate the file with the following values:
[Service]
CPUAffinity=0

Write out and close the file:
:wq

Reload systemd daemon:
sudo systemctl daemon-reload
Restart evodd service:
sudo systemctl restart evodd
Check evodd service status:
systemctl status evodd

Check process affinity:
tuna -t dd -P
Review the System's Hugepages Configuration
Check for any kernel configurations:
cat /proc/cmdline
Check the grub configuration file:
cat /etc/default/grub

Review the values in /proc/meminfo:
grep -i hugepages /proc/meminfo
Check the values using sysctl
sudo sysctl -a | grep vm.nr_hugepages

Check the value of /sys/kernel/mm/transparent_hugepage/enabled:
cat /sys/kernel/mm/transparent_hugepage/enabled
Configure a Hugepages Value and Disable Transparent Hugepages
Review grub file
sudo vi /etc/default/grub
Create a tuned profile called huge_profile
sudo mkdir /etc/tuned/huge_profile

Create profile configuration:
sudo vi /etc/tuned/huge_profile/tuned.conf

Populate the file with the following values:
[main]
include=virtual-guest

[sysctl]
vm.nr_hugepages=10

[vm]
transparent_hugepages=never

Write out and close the file:
:wq

Make profile active:
sudo tuned-adm profile huge_profile
Verify file and confirm it is active:
tuned-adm verify
tuned-adm active

Review the values in /proc/meminfo:
grep -i hugepages /proc/meminfo
Check the values using sysctl
sudo sysctl -a | grep vm.nr_hugepages
Check the value of /sys/kernel/mm/transparent_hugepage/enabled:
cat /sys/kernel/mm/transparent_hugepage/enabled

Reboot the Lab and Confirm Changes Persist
Reboot the system:
sudo shutdown -r now

Check the active tuned profile:
tuned-adm active
Confirm the changes were persistent after the reboot:
grep -i hugepages /proc/meminfo
sudo sysctl -a | grep vm.nr_hugepages
cat /sys/kernel/mm/transparent_hugepage/enabled

Confirm the process affinity:
tuna -t dd -P

Видео Tuning CPUs and Hugepages on a Linux System канала DEVOPS R US!