Use one lock server API per node (#13908)

This commit is only backporting an adapting to implement per node
locking API

Before this commit, each disk has its own locker API that needs to be
called when locking/unlock resources. This has a performance implication
if one deployment has many disks.

This PR changes locking calls to use one single endpoint per server
instead of an endpoint for each disk.  Meaning, if you want to lock
a resource, lock calls will be sent per server and not per node.

cmd/endpoint.go

@@ -207,6 +207,22 @@ type ZoneEndpoints struct {
 // EndpointServerSets - list of list of endpoints
 type EndpointServerSets []ZoneEndpoints
 
+// Localhost - returns the local hostname from list of endpoints
+func (l EndpointServerSets) Localhost() string {
+	for _, ep := range l {
+		for _, endpoint := range ep.Endpoints {
+			if endpoint.IsLocal {
+				u := &url.URL{
+					Scheme: endpoint.Scheme,
+					Host:   endpoint.Host,
+				}
+				return u.String()
+			}
+		}
+	}
+	return ""
+}
+
 // GetLocalZoneIdx returns the zone which endpoint belongs to locally.
 // if ep is remote this code will return -1 zoneIndex
 func (l EndpointServerSets) GetLocalZoneIdx(ep Endpoint) int {

cmd/erasure-sets.go

@@ -32,6 +32,7 @@ import (
 	"github.com/dchest/siphash"
 	"github.com/dustin/go-humanize"
 	"github.com/google/uuid"
+	"github.com/minio/minio-go/v7/pkg/set"
 	"github.com/minio/minio-go/v7/pkg/tags"
 	"github.com/minio/minio/cmd/config"
 	"github.com/minio/minio/cmd/logger"
@@ -289,10 +290,20 @@ func (s *erasureSets) monitorAndConnectEndpoints(ctx context.Context, monitorInt
 
 // GetAllLockers return a list of all lockers for all sets.
 func (s *erasureSets) GetAllLockers() []dsync.NetLocker {
-	allLockers := make([]dsync.NetLocker, s.setDriveCount*s.setCount)
-	for i, lockers := range s.erasureLockers {
-		for j, locker := range lockers {
-			allLockers[i*s.setDriveCount+j] = locker
+	var allLockers []dsync.NetLocker
+	lockEpSet := set.NewStringSet()
+	for _, lockers := range s.erasureLockers {
+		for _, locker := range lockers {
+			if locker == nil || !locker.IsOnline() {
+				// Skip any offline lockers.
+				continue
+			}
+			if lockEpSet.Contains(locker.String()) {
+				// Skip duplicate lockers.
+				continue
+			}
+			lockEpSet.Add(locker.String())
+			allLockers = append(allLockers, locker)
 		}
 	}
 	return allLockers
@@ -300,15 +311,8 @@ func (s *erasureSets) GetAllLockers() []dsync.NetLocker {
 
 func (s *erasureSets) GetLockers(setIndex int) func() ([]dsync.NetLocker, string) {
 	return func() ([]dsync.NetLocker, string) {
-		lockers := make([]dsync.NetLocker, s.setDriveCount)
+		lockers := make([]dsync.NetLocker, len(s.erasureLockers[setIndex]))
 		copy(lockers, s.erasureLockers[setIndex])
-		sort.Slice(lockers, func(i, j int) bool {
-			// re-order lockers with affinity for
-			// - non-local lockers
-			// - online lockers
-			// are used first
-			return !lockers[i].IsLocal() && lockers[i].IsOnline()
-		})
 		return lockers, s.erasureLockOwner
 	}
 }
@@ -386,14 +390,24 @@ func newErasureSets(ctx context.Context, endpoints Endpoints, storageDisks []Sto
 
 	for i := 0; i < setCount; i++ {
 		s.erasureDisks[i] = make([]StorageAPI, setDriveCount)
-		s.erasureLockers[i] = make([]dsync.NetLocker, setDriveCount)
+	}
+
+	var erasureLockers = map[string]dsync.NetLocker{}
+	for _, endpoint := range endpoints {
+		if _, ok := erasureLockers[endpoint.Host]; !ok {
+			erasureLockers[endpoint.Host] = newLockAPI(endpoint)
+		}
 	}
 
 	for i := 0; i < setCount; i++ {
+		var lockerEpSet = set.NewStringSet()
 		for j := 0; j < setDriveCount; j++ {
 			endpoint := endpoints[i*setDriveCount+j]
 			// Rely on endpoints list to initialize, init lockers and available disks.
-			s.erasureLockers[i][j] = newLockAPI(endpoint)
+			if locker, ok := erasureLockers[endpoint.Host]; ok && !lockerEpSet.Contains(endpoint.Host) {
+				lockerEpSet.Add(endpoint.Host)
+				s.erasureLockers[i] = append(s.erasureLockers[i], locker)
+			}
 			disk := storageDisks[i*setDriveCount+j]
 			if disk == nil {
 				continue

cmd/local-locker.go

@@ -47,12 +47,11 @@ func isWriteLock(lri []lockRequesterInfo) bool {
 // localLocker implements Dsync.NetLocker
 type localLocker struct {
 	mutex   sync.Mutex
-	endpoint Endpoint
 	lockMap map[string][]lockRequesterInfo
 }
 
 func (l *localLocker) String() string {
-	return l.endpoint.String()
+	return globalEndpoints.Localhost()
 }
 
 func (l *localLocker) canTakeUnlock(resources ...string) bool {
@@ -287,9 +286,8 @@ func (l *localLocker) expireOldLocks(interval time.Duration) {
 	}
 }
 
-func newLocker(endpoint Endpoint) *localLocker {
+func newLocker() *localLocker {
 	return &localLocker{
-		endpoint: endpoint,
 		lockMap: make(map[string][]lockRequesterInfo),
 	}
 }

cmd/lock-rest-client.go

@@ -34,7 +34,7 @@ import (
 // lockRESTClient is authenticable lock REST client
 type lockRESTClient struct {
 	restClient *rest.Client
-	endpoint   Endpoint
+	u          *url.URL
 }
 
 func toLockError(err error) error {
@@ -53,7 +53,7 @@ func toLockError(err error) error {
 
 // String stringer *dsync.NetLocker* interface compatible method.
 func (client *lockRESTClient) String() string {
-	return client.endpoint.String()
+	return client.u.String()
 }
 
 // Wrapper to restClient.Call to handle network errors, in case of network error the connection is marked disconnected
@@ -144,7 +144,7 @@ func (client *lockRESTClient) ForceUnlock(ctx context.Context, args dsync.LockAr
 
 func newLockAPI(endpoint Endpoint) dsync.NetLocker {
 	if endpoint.IsLocal {
-		return globalLockServers[endpoint]
+		return globalLockServer
 	}
 	return newlockRESTClient(endpoint)
 }
@@ -154,7 +154,7 @@ func newlockRESTClient(endpoint Endpoint) *lockRESTClient {
 	serverURL := &url.URL{
 		Scheme: endpoint.Scheme,
 		Host:   endpoint.Host,
-		Path:   pathJoin(lockRESTPrefix, endpoint.Path, lockRESTVersion),
+		Path:   pathJoin(lockRESTPrefix, lockRESTVersion),
 	}
 
 	var tlsConfig *tls.Config
@@ -179,5 +179,11 @@ func newlockRESTClient(endpoint Endpoint) *lockRESTClient {
 		return !errors.Is(err, context.DeadlineExceeded) && !errors.As(err, &ne)
 	}
 
-	return &lockRESTClient{endpoint: endpoint, restClient: restClient}
+	return &lockRESTClient{
+		u: &url.URL{
+			Scheme: endpoint.Scheme,
+			Host:   endpoint.Host,
+		},
+		restClient: restClient,
+	}
 }

cmd/lock-rest-server.go

@@ -21,7 +21,6 @@ import (
 	"context"
 	"errors"
 	"net/http"
-	"path"
 	"sort"
 	"strconv"
 	"time"
@@ -264,26 +263,18 @@ func lockMaintenance(ctx context.Context) {
 			// Reset the timer for next cycle.
 			lkTimer.Reset(lockMaintenanceInterval)
 
-			for _, lockServer := range globalLockServers {
-				lockServer.expireOldLocks(lockValidityDuration)
-			}
+			globalLockServer.expireOldLocks(lockValidityDuration)
 		}
 	}
 }
 
 // registerLockRESTHandlers - register lock rest router.
-func registerLockRESTHandlers(router *mux.Router, endpointServerSets EndpointServerSets) {
-	for _, ep := range endpointServerSets {
-		for _, endpoint := range ep.Endpoints {
-			if !endpoint.IsLocal {
-				continue
-			}
-
+func registerLockRESTHandlers(router *mux.Router) {
 	lockServer := &lockRESTServer{
-				ll: newLocker(endpoint),
+		ll: newLocker(),
 	}
 
-			subrouter := router.PathPrefix(path.Join(lockRESTPrefix, endpoint.Path)).Subrouter()
+	subrouter := router.PathPrefix(lockRESTPrefix).Subrouter()
 	subrouter.Methods(http.MethodPost).Path(lockRESTVersionPrefix + lockRESTMethodHealth).HandlerFunc(httpTraceHdrs(lockServer.HealthHandler))
 	subrouter.Methods(http.MethodPost).Path(lockRESTVersionPrefix + lockRESTMethodRefresh).HandlerFunc(httpTraceHdrs(lockServer.RefreshHandler))
 	subrouter.Methods(http.MethodPost).Path(lockRESTVersionPrefix + lockRESTMethodLock).HandlerFunc(httpTraceHdrs(lockServer.LockHandler))
@@ -292,9 +283,7 @@ func registerLockRESTHandlers(router *mux.Router, endpointServerSets EndpointSer
 	subrouter.Methods(http.MethodPost).Path(lockRESTVersionPrefix + lockRESTMethodRUnlock).HandlerFunc(httpTraceHdrs(lockServer.RUnlockHandler))
 	subrouter.Methods(http.MethodPost).Path(lockRESTVersionPrefix + lockRESTMethodForceUnlock).HandlerFunc(httpTraceHdrs(lockServer.ForceUnlockHandler))
 
-			globalLockServers[endpoint] = lockServer.ll
-		}
-	}
+	globalLockServer = lockServer.ll
 
 	go lockMaintenance(GlobalContext)
 }

cmd/namespace-lock.go

@@ -34,7 +34,7 @@ import (
 )
 
 // local lock servers
-var globalLockServers = make(map[Endpoint]*localLocker)
+var globalLockServer *localLocker
 
 // RWLocker - locker interface to introduce GetRLock, RUnlock.
 type RWLocker interface {

cmd/notification.go

@@ -521,10 +521,7 @@ func (sys *NotificationSys) GetLocks(ctx context.Context, r *http.Request) []*Pe
 	}
 	// Once we have received all the locks currently used from peers
 	// add the local peer locks list as well.
-	llockers := make(GetLocksResp, 0, len(globalLockServers))
-	for _, llocker := range globalLockServers {
-		llockers = append(llockers, llocker.DupLockMap())
-	}
+	llockers := GetLocksResp{globalLockServer.DupLockMap()}
 	locksResp = append(locksResp, &PeerLocks{
 		Addr:  getHostName(r),
 		Locks: llockers,

cmd/peer-rest-server.go

@@ -48,10 +48,7 @@ func (s *peerRESTServer) GetLocksHandler(w http.ResponseWriter, r *http.Request)
 
 	ctx := newContext(r, w, "GetLocks")
 
-	llockers := make(GetLocksResp, 0, len(globalLockServers))
-	for _, llocker := range globalLockServers {
-		llockers = append(llockers, llocker.DupLockMap())
-	}
+	llockers := GetLocksResp{globalLockServer.DupLockMap()}
 	logger.LogIf(ctx, gob.NewEncoder(w).Encode(llockers))
 
 	w.(http.Flusher).Flush()

cmd/routers.go

@@ -34,7 +34,7 @@ func registerDistErasureRouters(router *mux.Router, endpointServerSets EndpointS
 	registerBootstrapRESTHandlers(router)
 
 	// Register distributed namespace lock routers.
-	registerLockRESTHandlers(router, endpointServerSets)
+	registerLockRESTHandlers(router)
 }
 
 // List of some generic handlers which are applied for all incoming requests.