The purpose of this post is to explain the steps to disable NUMA on servers which use the EFI boot loader.
GRUB 2 is the default EFI-mode boot loader, so the steps are based on GRUB2.
1. Take a backup of /etc/default/grub configuration file.
# cp -p /etc/default/grub /etc/default/grub_backup
2. Edit /etc/default/grub file and replace numa=on to numa=off.
# vi /etc/default/grub
..
GRUB_CMDLINE_LINUX_DEFAULT="root=LABEL=DBSYS bootarea=dbsys bootfrom=BOOT ro loglevel=7 panic=60 debug pci=noaer log_buf_len=1m nmi_watchdog=0 transparent_hugepage=never rd_NO_PLYMOUTH audit=1 console=tty1 console=ttyS0,115200n8 crashkernel=448M@128M numa=off
3. Run the following command to rebuild the grub.cfg:
# grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
4. Reboot the server to make the changes effect.
# shutdown -r now
NUMA STATUS
numactl command can be used to check the status of NUMA
# numactl -H | grep available available: 8 nodes (0-7)
– or –
# numactl -H | grep available available: 2 nodes (0-1)
If the number of available nodes is “2 nodes (0-1)” or “8 nodes (0-7)” then NUMA is enabled. If the number of available nodes is “1 nodes (0)” then NUMA is not enabled.