X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/6346a7c4c0cb5d7e8c5f01392b6cc64d329b68ec..733e8c44dacf230d605fe6e5ea3f95f0abb8d823:/services/crunch-dispatch-slurm/slurm.go

diff --git a/services/crunch-dispatch-slurm/slurm.go b/services/crunch-dispatch-slurm/slurm.go
index 735e057e25..791f294df1 100644
--- a/services/crunch-dispatch-slurm/slurm.go
+++ b/services/crunch-dispatch-slurm/slurm.go
@@ -13,13 +13,22 @@ import (
 )
 
 type Slurm interface {
+	Batch(script io.Reader, args []string) error
 	Cancel(name string) error
-	Renice(name string, nice int64) error
 	QueueCommand(args []string) *exec.Cmd
-	Batch(script io.Reader, args []string) error
+	Release(name string) error
+	Renice(name string, nice int64) error
+}
+
+type slurmCLI struct {
+	runSemaphore chan bool
 }
 
-type slurmCLI struct{}
+func NewSlurmCLI() *slurmCLI {
+	return &slurmCLI{
+		runSemaphore: make(chan bool, 3),
+	}
+}
 
 func (scli *slurmCLI) Batch(script io.Reader, args []string) error {
 	return scli.run(script, "sbatch", args)
@@ -54,11 +63,17 @@ func (scli *slurmCLI) QueueCommand(args []string) *exec.Cmd {
 	return exec.Command("squeue", args...)
 }
 
+func (scli *slurmCLI) Release(name string) error {
+	return scli.run(nil, "scontrol", []string{"release", "Name=" + name})
+}
+
 func (scli *slurmCLI) Renice(name string, nice int64) error {
 	return scli.run(nil, "scontrol", []string{"update", "JobName=" + name, fmt.Sprintf("Nice=%d", nice)})
 }
 
 func (scli *slurmCLI) run(stdin io.Reader, prog string, args []string) error {
+	scli.runSemaphore <- true
+	defer func() { <-scli.runSemaphore }()
 	cmd := exec.Command(prog, args...)
 	cmd.Stdin = stdin
 	out, err := cmd.CombinedOutput()