-
-// SlurmNodeTypeFeatureKludge ensures SLURM accepts every instance
-// type name as a valid feature name, even if no instances of that
-// type have appeared yet.
-//
-// It takes advantage of some SLURM peculiarities:
-//
-// (1) A feature is valid after it has been offered by a node, even if
-// it is no longer offered by any node. So, to make a feature name
-// valid, we can add it to a dummy node ("compute0"), then remove it.
-//
-// (2) To test whether a set of feature names are valid without
-// actually submitting a job, we can call srun --test-only with the
-// desired features.
-//
-// SlurmNodeTypeFeatureKludge does a test-and-fix operation
-// immediately, and then periodically, in case slurm restarts and
-// forgets the list of valid features. It never returns (unless there
-// are no node types configured, in which case it returns
-// immediately), so it should generally be invoked with "go".
-func SlurmNodeTypeFeatureKludge(cc *arvados.Cluster) {
- if len(cc.InstanceTypes) == 0 {
- return
- }
- var features []string
- for _, it := range cc.InstanceTypes {
- features = append(features, "instancetype="+it.Name)
- }
- for {
- slurmKludge(features)
- time.Sleep(2 * time.Second)
- }
-}
-
-const slurmDummyNode = "compute0"
-
-func slurmKludge(features []string) {
- allFeatures := strings.Join(features, ",")
-
- cmd := exec.Command("sinfo", "--nodes="+slurmDummyNode, "--format=%f", "--noheader")
- out, err := cmd.CombinedOutput()
- if err != nil {
- log.Printf("running %q %q: %s (output was %q)", cmd.Path, cmd.Args, err, out)
- return
- }
- if string(out) == allFeatures+"\n" {
- // Already configured correctly, nothing to do.
- return
- }
-
- log.Printf("configuring node %q with all node type features", slurmDummyNode)
- cmd = exec.Command("scontrol", "update", "NodeName="+slurmDummyNode, "Features="+allFeatures)
- log.Printf("running: %q %q", cmd.Path, cmd.Args)
- out, err = cmd.CombinedOutput()
- if err != nil {
- log.Printf("error: scontrol: %s (output was %q)", err, out)
- }
-}