Updated: 28 September 2026 · Applies to: AlmaLinux and Rocky Linux 9 and 10, RHEL 9 and 10 (grubby, tuned), Ubuntu 24.04 and 26.04, Debian 13
Transparent Huge Pages (THP) let the kernel use 2 MB memory pages instead of 4 KB ones, which speeds up many programs. Some databases work better without them, and their documentation says so: for example MongoDB 7.0 and earlier, Redis, and Oracle Database. Only disable THP if your software asks for it: MongoDB 8.0 and later, for instance, asks for THP to be enabled.
1. Check the current setting
cat /sys/kernel/mm/transparent_hugepage/enabled cat /sys/kernel/mm/transparent_hugepage/defrag
The active value is in square brackets. An AlmaLinux 9 server we checked shows [always] madvise never: THP is used for all memory. Debian 13 kernels also default to always; Ubuntu 24.04 kernels default to madvise, where only programs that ask for huge pages get them. never switches THP off.
2. Switch it off now (until reboot)
echo never > /sys/kernel/mm/transparent_hugepage/enabled echo never > /sys/kernel/mm/transparent_hugepage/defrag
Restart the database afterwards; memory it already uses keeps its huge pages.
3. Switch it off permanently
AlmaLinux, Rocky Linux and RHEL: add a kernel parameter to all boot entries, then reboot:
grubby --update-kernel=ALL --args="transparent_hugepage=never" reboot
If the server uses the tuned service, make sure its active profile does not switch THP back on: check with tuned-adm active, and look for transparent_hugepages in that profile's tuned.conf.
Ubuntu and Debian: add transparent_hugepage=never to GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub, then run update-grub and reboot.
4. Check after the reboot
cat /proc/cmdline cat /sys/kernel/mm/transparent_hugepage/enabled
The second command should show always madvise [never].
madvise instead of never
Setting transparent_hugepage=madvise is often the better compromise: applications that benefit from huge pages can still request them, while others, such as the database, are not affected. Check your software's documentation for its recommendation.
Official documentation: Transparent Hugepage Support (Linux kernel).
