···

       
3
       
 
       
{

     

       
4
       
 
       
  name = "systemd-oomd";

     

       
5
       
 
       


     

       
0
       
 
       

     

       
0
       
 
       

     

       
6
       
 
       
  nodes.machine = { pkgs, ... }: {

     

       
7
       
-
       
    systemd.oomd.extraConfig.DefaultMemoryPressureDurationSec = "1s"; # makes the test faster

     

       
8
       
-
       
    # Kill cgroups when more than 1% pressure is encountered

     

       
9
       
-
       
    systemd.slices."-".sliceConfig = {

     

       
10
       
-
       
      ManagedOOMMemoryPressure = "kill";

     

       
11
       
-
       
      ManagedOOMMemoryPressureLimit = "1%";

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
12
       
 
       
    };

     

       
13
       
-
       
    # A service to bring the system under memory pressure

     

       
14
       
-
       
    systemd.services.testservice = {

     

       
15
       
-
       
      serviceConfig.ExecStart = "${pkgs.coreutils}/bin/tail /dev/zero";

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
16
       
 
       
    };

     

       
17
       
-
       
    # Do not kill the backdoor

     

       
18
       
-
       
    systemd.services.backdoor.serviceConfig.ManagedOOMMemoryPressure = "auto";

     

       
19
       
 
       


     

       
20
       
-
       
    virtualisation.memorySize = 1024;

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
21
       
 
       
  };

     

       
22
       
 
       


     

       
23
       
 
       
  testScript = ''

     

       
24
       
-
       
    # Start the system

     

       
25
       
 
       
    machine.wait_for_unit("multi-user.target")

     

       
26
       
 
       
    machine.succeed("oomctl")

     

       
27
       
 
       


     

       
28
       
-
       
    # Bring the system into memory pressure

     

       
29
       
-
       
    machine.succeed("echo 0 > /proc/sys/vm/panic_on_oom")  # NixOS tests kill the VM when the OOM killer is invoked - override this

     

       
30
       
-
       
    machine.succeed("systemctl start testservice")

     

       
0
       
 
       

     

       
31
       
 
       


     

       
32
       
-
       
    # Wait for oomd to kill something

     

       
33
       
-
       
    # Matches these lines:

     

       
34
       
-
       
    # systemd-oomd[508]: Killed /system.slice/systemd-udevd.service due to memory pressure for / being 3.26% > 1.00% for > 1s with reclaim activity

     

       
35
       
-
       
    machine.wait_until_succeeds("journalctl -b | grep -q 'due to memory pressure for'")

     

       
36
       
 
       
  '';

     

       
37
       
 
       
})

     

···

       
3
       
 
       
{

     

       
4
       
 
       
  name = "systemd-oomd";

     

       
5
       
 
       


     

       
6
       
+
       
  # This test is a simplified version of systemd's testsuite-55.

     

       
7
       
+
       
  # https://github.com/systemd/systemd/blob/v251/test/units/testsuite-55.sh

     

       
8
       
 
       
  nodes.machine = { pkgs, ... }: {

     

       
9
       
+
       
    # Limit VM resource usage.

     

       
10
       
+
       
    virtualisation.memorySize = 1024;

     

       
11
       
+
       
    systemd.oomd.extraConfig.DefaultMemoryPressureDurationSec = "1s";

     

       
12
       
+
       


     

       
13
       
+
       
    systemd.slices.workload = {

     

       
14
       
+
       
      description = "Test slice for memory pressure kills";

     

       
15
       
+
       
      sliceConfig = {

     

       
16
       
+
       
        MemoryAccounting = true;

     

       
17
       
+
       
        ManagedOOMMemoryPressure = "kill";

     

       
18
       
+
       
        ManagedOOMMemoryPressureLimit = "10%";

     

       
19
       
+
       
      };

     

       
20
       
 
       
    };

     

       
21
       
+
       


     

       
22
       
+
       
    systemd.services.testbloat = {

     

       
23
       
+
       
      description = "Create a lot of memory pressure";

     

       
24
       
+
       
      serviceConfig = {

     

       
25
       
+
       
        Slice = "workload.slice";

     

       
26
       
+
       
        MemoryHigh = "5M";

     

       
27
       
+
       
        ExecStart = "${pkgs.coreutils}/bin/tail /dev/zero";

     

       
28
       
+
       
      };

     

       
29
       
 
       
    };

     

       
0
       
 
       

     

       
0
       
 
       

     

       
30
       
 
       


     

       
31
       
+
       
    systemd.services.testchill = {

     

       
32
       
+
       
      description = "No memory pressure";

     

       
33
       
+
       
      serviceConfig = {

     

       
34
       
+
       
        Slice = "workload.slice";

     

       
35
       
+
       
        MemoryHigh = "3M";

     

       
36
       
+
       
        ExecStart = "${pkgs.coreutils}/bin/sleep infinity";

     

       
37
       
+
       
      };

     

       
38
       
+
       
    };

     

       
39
       
 
       
  };

     

       
40
       
 
       


     

       
41
       
 
       
  testScript = ''

     

       
42
       
+
       
    # Start the system.

     

       
43
       
 
       
    machine.wait_for_unit("multi-user.target")

     

       
44
       
 
       
    machine.succeed("oomctl")

     

       
45
       
 
       


     

       
46
       
+
       
    machine.succeed("systemctl start testchill.service")

     

       
47
       
+
       
    with subtest("OOMd should kill the bad service"):

     

       
48
       
+
       
        machine.fail("systemctl start --wait testbloat.service")

     

       
49
       
+
       
        assert machine.get_unit_info("testbloat.service")["Result"] == "oom-kill"

     

       
50
       
 
       


     

       
51
       
+
       
    with subtest("Service without memory pressure should be untouched"):

     

       
52
       
+
       
        machine.require_unit_state("testchill.service", "active")

     

       
0
       
 
       

     

       
0
       
 
       

     

       
53
       
 
       
  '';

     

       
54
       
 
       
})