TALM image precaching executes a disk space check on the managed cluster before precaching begins. When a low disk space condition:

disk space free is less than ((15% capacity in KB) - 15GB) 

TALM should report report the error "not enough space for precaching" 

In TALM build 4.13.0-42 this error is not reported in the precaching pod logs.

4.13.0-42

Always

1.Simulate a low disk space condition on the managed cluster. Use fallocate to create a file of a size calculated to force free disk space to be (85% - 15GB) of total capacity. 
2. Create and enable a policy and CGU that will trigger image precaching 
3. Monitor the precache pod logs on the managed cluster. 

CGU status on hub:

  - lastTransitionTime: "2023-02-27T20:26:45Z"
    message: Precaching failed for all clusters
    reason: Failed
    status: "False"
    type: PrecachingSuceeded
...
  precaching:
    spec:
...
    status:
      ocp-edge87: UnrecoverableError



Log from precache pod on managed cluster

$ oc logs  -n openshift-talo-pre-cache pre-cache-rllmj --follow
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  3262    0  3262    0     0  74136      0 --:--:-- --:--:-- --:--:-- 74136
highThresholdPercent: 85 diskSize:937156932 used:781047416

TALM should report report the error "not enough space for precaching"