Meziantou.Framework

Getting started

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Install the package

Add the Meziantou.Framework.Unix.ControlGroups package to a project:

dotnet package add Meziantou.Framework.Unix.ControlGroups

The examples of this documentation omit the using directives: they need using Meziantou.Framework.Unix.ControlGroups;, and using System.Diagnostics; for Process. They change the control groups of the machine, so they need Linux and root.

Run a process with limited resources

// Controllers are enabled on a parent cgroup, and apply to its children
var parent = CGroup2.Root.CreateOrGetChild("myapp");
parent.SetControllers("cpu", "memory", "pids");

// The processes go into a child cgroup, which holds the limits
var worker = parent.CreateOrGetChild("worker");
worker.SetCpuMax(50_000, 100_000);         // half of a CPU
worker.SetMemoryMax(256L * 1024 * 1024);   // 256 MB
worker.SetPidsMax(20);                     // 20 processes

using var process = Process.Start("sleep", "60");
worker.AssociateProcess(process);
Assert.Contains(process.Id, worker.GetProcesses());

// A cgroup can be deleted only when it has no process and no child cgroup
worker.Kill();
process.WaitForExit();
worker.Delete();
parent.Delete();
  • CreateOrGetChild creates a control group, a folder of /sys/fs/cgroup, or returns the existing one.
  • SetControllers enables the controllers on parent, so its children get the files that set the limits. The controllers must be enabled on the parent of parent too: the root enables the common controllers on most distributions.
  • parent holds no process, and worker holds no child: a control group cannot do both, except the root.
  • The limits apply to all the processes of worker, together, including the processes they start.
  • Kill stops every process of the control group. Delete removes an empty control group.

Moving the current process into a control group limits the application itself: call AssociateProcess(Environment.ProcessId).

Next steps