kvsever: introduce some testing knobs for node liveness

Release note: None

pkg/base/testing_knobs.go

@@ -31,6 +31,7 @@ type TestingKnobs struct {
 	DistSQL              ModuleTestingKnobs
 	SQLEvalContext       ModuleTestingKnobs
 	RegistryLiveness     ModuleTestingKnobs
+	NodeLiveness         ModuleTestingKnobs
 	Server               ModuleTestingKnobs
 	TenantTestingKnobs   ModuleTestingKnobs
 	JobsTestingKnobs     ModuleTestingKnobs

pkg/kv/kvserver/testing_knobs.go

@@ -13,6 +13,7 @@ package kvserver
 import (
 	"time"
 
+	"github.com/cockroachdb/cockroach/pkg/base"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/kvserverbase"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/tenantrate"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/txnwait"
@@ -250,3 +251,19 @@ type StoreTestingKnobs struct {
 
 // ModuleTestingKnobs is part of the base.ModuleTestingKnobs interface.
 func (*StoreTestingKnobs) ModuleTestingKnobs() {}
+
+// NodeLivenessTestingKnobs allows tests to override some node liveness
+// controls. When set, fields ultimately affect the NodeLivenessOptions used by
+// the cluster.
+type NodeLivenessTestingKnobs struct {
+	// LivenessDuration overrides a liveness record's life time.
+	LivenessDuration time.Duration
+	// RenewalDuration specifies how long before the expiration a record is
+	// heartbeated. If LivenessDuration is set, this should probably be set too.
+	RenewalDuration time.Duration
+}
+
+var _ base.ModuleTestingKnobs = NodeLivenessTestingKnobs{}
+
+// ModuleTestingKnobs implements the base.ModuleTestingKnobs interface.
+func (NodeLivenessTestingKnobs) ModuleTestingKnobs() {}

pkg/server/server.go

@@ -407,6 +407,15 @@ func NewServer(cfg Config, stopper *stop.Stopper) (*Server, error) {
 	db := kv.NewDBWithContext(cfg.AmbientCtx, tcsFactory, clock, dbCtx)
 
 	nlActive, nlRenewal := cfg.NodeLivenessDurations()
+	if knobs := cfg.TestingKnobs.NodeLiveness; knobs != nil {
+		nlKnobs := knobs.(kvserver.NodeLivenessTestingKnobs)
+		if duration := nlKnobs.LivenessDuration; duration != 0 {
+			nlActive = duration
+		}
+		if duration := nlKnobs.RenewalDuration; duration != 0 {
+			nlRenewal = duration
+		}
+	}
 
 	nodeLiveness := kvserver.NewNodeLiveness(kvserver.NodeLivenessOptions{
 		AmbientCtx:              cfg.AmbientCtx,