CoreOS provides no [[package manager]], requringrequiring all applications to run inside their containers, using [[Docker (software)|Docker]] and its underlying [[Linux Containers]] (LXC) [[operating system-level virtualization]] technology for running multiple isolated Linux systems (containers) on a single control host (CoreOS instance). That way, resource partitioning is performed through multiple isolated [[userspace]] instances, instead of using a [[hypervisor]] and providing full-fledged [[virtual machine]]s. This approach relies on the [[Linux kernel]]'s [[cgroups]] functionality, which provides [[namespace isolation]] and abilities to limit, account and isolate [[Resource (computer science)|resource usage]] ([[CPU]], memory, disk [[I/O]], etc.) of [[process group]]s.<ref name="linux.com-737364" /><ref name="coreos-using" /><ref>{{Cite web
| url = https://coreos.com/using-coreos/docker/
| title = Using docker with CoreOS | work = CoreOS documentation
