aarch64 (ARM) 64k Page Size Kernel Support¶

Release Timeframe: December 2025
Affected Versions: Rocky Linux 8, 9, and 10
Architecture: aarch64 (ARM) only
Type: New Feature

Overview¶

CIQ SIG/Cloud Next now provides a 64k page size kernel (kernel-64k) for aarch64 (ARM) architecture, along with kernel modules (kmods) built specifically for it. If you install kernel-64k on a system with existing SCN kmods, the corresponding 64k-compatible kmods are automatically installed alongside them.

After rebooting into the 64k kernel, the kmods will be available and functional.

Prerequisites¶

CIQ SIG/Cloud Next enabled at default priority

Installation¶

Installing the 64k Kernel¶

Install the kernel-64k package using dnf:

dnf install kernel-64k

The system will automatically install any required 64k-compatible kmods alongside the kernel.

Setting the 64k Kernel as Default¶

Installing kernel-64k does not automatically make it the default boot kernel. To set it as default, run the following commands:

k=$(echo /boot/vmlinuz*64k)
grubby --set-default=$k \
       --args="crashkernel=2G-:640M"

Note: A simpler version (grubby --set-default=$(echo /boot/vmlinuz*64k)) will work for most configurations, but if you're using a crash kernel, the full command above is necessary.

Reboot¶

Reboot the system to boot into the 64k kernel:

reboot

Post-Installation Best Practices¶

Removing the Standard Kernel¶

After successfully rebooting into the 64k kernel and verifying your workloads function correctly, it's recommended to remove the standard (non-64k) kernel to prevent accidentally booting into the wrong kernel:

# Verify you're running the 64k kernel
uname -r

# List installed kernels
rpm -qa kernel kernel-64k

# Remove the standard kernel (example)
dnf remove kernel-<version>

Important: Only remove the standard kernel after confirming the 64k kernel works correctly for your workloads.

Tested Configuration¶

This feature has been validated on the Google Cloud C4A metal instance family using:

The 64k page size kernel
kmod-idpf-irdma (provides an updated IDPF driver used by HPC workloads)

Known Limitations¶

Non-default kernel variants (including kernel-64k) receive less intensive kmod testing compared to the default kernel. Users should validate their specific workloads accordingly.