What is TurboKernel?

TurboKernel is the performance-tuned Linux kernel TurboStack builds and maintains for its servers, kept current through a signed update pipeline.

TurboKernel is the Linux kernel that TurboStack servers run. Instead of the distribution's general-purpose kernel, Hosted Power compiles and tunes one for the hardware and the workloads TurboStack actually runs: web servers, PHP processes, databases and caches under concurrent load.

It is installed by default and there is nothing to configure. This page explains what it changes, so the name in your monitoring means something.

What it changes

A general-purpose kernel is built to run acceptably on everything from a laptop to a mainframe. TurboKernel drops that compromise and is built for one kind of machine:

  • Built for modern server processors. It targets a recent instruction-set level, so the compiler can use CPU features that a general-purpose build cannot assume are present.

  • Tuned scheduling. Process scheduling is adjusted for many short requests competing at once, which is what a web server does, rather than for a desktop.

  • Tuned memory, network and storage paths. These are the paths a busy site spends its time in. Network congestion control in particular is set to a newer algorithm that keeps latency low when a link is busy.

  • It enables TurboRAM's better compression. The memory compression that TurboRAM uses needs a recent kernel feature. On TurboKernel it can compress with a fast algorithm first and re-compress cold pages more densely afterwards, which a stock kernel cannot do.

Staying current

Running a custom kernel is only safe if it keeps up with upstream security fixes. TurboKernel is rebuilt and published continuously, and servers pick up new builds from a signed package repository, so the packages are verified before they are installed. You do not have to track kernel advisories or schedule the updates.

A server reboots once when it first moves onto TurboKernel. After that, new TurboKernel versions are installed onto disk during normal deployments and take effect at the next planned reboot, so an upgrade never reboots a server unexpectedly.

When a server does not run it

TurboKernel needs a processor that supports the instruction set it is built for. Almost all current server hardware does, but an older machine, or a virtual machine whose exposed CPU model hides those features, does not. TurboStack checks this before installing anything: a server that cannot boot the kernel keeps the distribution kernel instead. Nothing is broken by this, and the server runs normally

  • it simply does not get the extra tuning.

© 2026 Hosted Power — TurboStack