From d1aff26b4f7fd8f4516f90ba29595b5bc511cec9 Mon Sep 17 00:00:00 2001
From: Alex Dadgar <alex.dadgar@gmail.com>
Date: Sat, 20 Feb 2016 16:11:29 -0800
Subject: [PATCH] Add force node gc

---
 nomad/core_sched.go      | 20 ++++++++++++++------
 nomad/core_sched_test.go |  2 --
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/nomad/core_sched.go b/nomad/core_sched.go
index 9c4cc4fa9..4fbe54e02 100644
--- a/nomad/core_sched.go
+++ b/nomad/core_sched.go
@@ -240,12 +240,20 @@ func (c *CoreScheduler) nodeGC(eval *structs.Evaluation) error {
 		return err
 	}
 
-	// Compute the old threshold limit for GC using the FSM
-	// time table.  This is a rough mapping of a time to the
-	// Raft index it belongs to.
-	tt := c.srv.fsm.TimeTable()
-	cutoff := time.Now().UTC().Add(-1 * c.srv.config.NodeGCThreshold)
-	oldThreshold := tt.NearestIndex(cutoff)
+	var oldThreshold uint64
+	if eval.TriggeredBy == structs.EvalTriggerForceGC {
+		// The GC was forced, so set the threshold to its maximum so everything
+		// will GC.
+		oldThreshold = math.MaxUint64
+		c.srv.logger.Println("[DEBUG] sched.core: forced node GC")
+	} else {
+		// Compute the old threshold limit for GC using the FSM
+		// time table.  This is a rough mapping of a time to the
+		// Raft index it belongs to.
+		tt := c.srv.fsm.TimeTable()
+		cutoff := time.Now().UTC().Add(-1 * c.srv.config.NodeGCThreshold)
+		oldThreshold = tt.NearestIndex(cutoff)
+	}
 	c.srv.logger.Printf("[DEBUG] sched.core: node GC: scanning before index %d (%v)",
 		oldThreshold, c.srv.config.NodeGCThreshold)
 
diff --git a/nomad/core_sched_test.go b/nomad/core_sched_test.go
index f5eefafd3..7ef97a510 100644
--- a/nomad/core_sched_test.go
+++ b/nomad/core_sched_test.go
@@ -190,7 +190,6 @@ func TestCoreScheduler_NodeGC_Force(t *testing.T) {
 
 	// Attempt the GC
 	gc := s1.forceCoreJobEval(structs.CoreJobNodeGC)
-	gc.ModifyIndex = 2000
 	err = core.Process(gc)
 	if err != nil {
 		t.Fatalf("err: %v", err)
@@ -377,7 +376,6 @@ func TestCoreScheduler_JobGC_Force(t *testing.T) {
 
 		// Attempt the GC
 		gc := s1.forceCoreJobEval(structs.CoreJobJobGC)
-		gc.ModifyIndex = 2000
 		err = core.Process(gc)
 		if err != nil {
 			t.Fatalf("test(%s) err: %v", test.test, err)