feat: allow decom of multiple pools (#16416)

cmd/admin-handlers-pools.go

@@ -22,6 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
+	"strings"
 
 	"github.com/gorilla/mux"
 	"github.com/minio/minio/internal/logger"
@@ -49,28 +50,53 @@ func (a adminAPIHandlers) StartDecommission(w http.ResponseWriter, r *http.Reque
 		return
 	}
 
-	pools, ok := objectAPI.(*erasureServerPools)
-	if !ok {
+	z, ok := objectAPI.(*erasureServerPools)
+	if !ok || len(z.serverPools) == 1 {
 		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrNotImplemented), r.URL)
 		return
 	}
 
-	if pools.IsRebalanceStarted() {
-		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, errDecommissionRebalanceAlreadyRunning), r.URL)
+	if z.IsDecommissionRunning() {
+		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, errDecommissionAlreadyRunning), r.URL)
+		return
+	}
+
+	if z.IsRebalanceStarted() {
+		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminRebalanceAlreadyStarted), r.URL)
 		return
 	}
 
 	vars := mux.Vars(r)
 	v := vars["pool"]
 
-	idx := globalEndpoints.GetPoolIdx(v)
+	pools := strings.Split(v, ",")
+	poolIndices := make([]int, 0, len(pools))
+
+	for _, pool := range pools {
+		idx := globalEndpoints.GetPoolIdx(pool)
 		if idx == -1 {
 			// We didn't find any matching pools, invalid input
 			writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, errInvalidArgument), r.URL)
 			return
 		}
+		var pool *erasureSets
+		for pidx := range z.serverPools {
+			if pidx == idx {
+				pool = z.serverPools[idx]
+				break
+			}
+		}
+		if pool == nil {
+			// We didn't find any matching pools, invalid input
+			writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, errInvalidArgument), r.URL)
+			return
+		}
 
-	if ep := globalEndpoints[idx].Endpoints[0]; !ep.IsLocal {
+		poolIndices = append(poolIndices, idx)
+	}
+
+	if len(poolIndices) > 0 && globalEndpoints[poolIndices[0]].Endpoints[0].IsLocal {
+		ep := globalEndpoints[poolIndices[0]].Endpoints[0]
 		for nodeIdx, proxyEp := range globalProxyEndpoints {
 			if proxyEp.Endpoint.Host == ep.Host {
 				if proxyRequestByNodeIndex(ctx, w, r, nodeIdx) {
@@ -80,7 +106,7 @@ func (a adminAPIHandlers) StartDecommission(w http.ResponseWriter, r *http.Reque
 		}
 	}
 
-	if err := pools.Decommission(r.Context(), idx); err != nil {
+	if err := z.Decommission(r.Context(), poolIndices...); err != nil {
 		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
 		return
 	}

cmd/erasure-server-pool-decom.go

@@ -126,7 +126,7 @@ type poolMeta struct {
 
 // A decommission resumable tells us if decommission is worth
 // resuming upon restart of a cluster.
-func (p *poolMeta) returnResumablePools(n int) []PoolStatus {
+func (p *poolMeta) returnResumablePools() []PoolStatus {
 	var newPools []PoolStatus
 	for _, pool := range p.Pools {
 		if pool.Decommission == nil {
@@ -139,11 +139,8 @@ func (p *poolMeta) returnResumablePools(n int) []PoolStatus {
 			continue
 		} // In all other situations we need to resume
 		newPools = append(newPools, pool)
-		if n > 0 && len(newPools) == n {
+	}
 	return newPools
-		}
-	}
-	return nil
 }
 
 func (p *poolMeta) DecommissionComplete(idx int) bool {
@@ -251,18 +248,6 @@ var (
 )
 
 func (p *poolMeta) Decommission(idx int, pi poolSpaceInfo) error {
-	for i, pool := range p.Pools {
-		if idx == i {
-			continue
-		}
-		if pool.Decommission != nil {
-			// Do not allow multiple decommissions at the same time.
-			// We shall for now only allow one pool decommission at
-			// a time.
-			return fmt.Errorf("%w at index: %d", errDecommissionAlreadyRunning, i)
-		}
-	}
-
 	// Return an error when there is decommission on going - the user needs
 	// to explicitly cancel it first in order to restart decommissioning again.
 	if p.Pools[idx].Decommission != nil &&
@@ -510,7 +495,6 @@ func (z *erasureServerPools) Init(ctx context.Context) error {
 	z.StartRebalance()
 
 	meta := poolMeta{}
-
 	if err := meta.load(ctx, z.serverPools[0], z.serverPools); err != nil {
 		return err
 	}
@@ -524,38 +508,38 @@ func (z *erasureServerPools) Init(ctx context.Context) error {
 	if !update {
 		z.poolMeta = meta
 
-		// We are only supporting single pool decommission at this time
-		// so it makes sense to only resume single pools at any given
-		// time, in future meta.returnResumablePools() might take
-		// '-1' as argument to decommission multiple pools at a time
-		// but this is not a priority at the moment.
-		for _, pool := range meta.returnResumablePools(1) {
+		pools := meta.returnResumablePools()
+		poolIndices := make([]int, 0, len(pools))
+		for _, pool := range pools {
 			idx := globalEndpoints.GetPoolIdx(pool.CmdLine)
 			if idx == -1 {
 				return fmt.Errorf("unexpected state present for decommission status pool(%s) not found", pool.CmdLine)
 			}
-			if globalEndpoints[idx].Endpoints[0].IsLocal {
-				go func(pool PoolStatus) {
+			poolIndices = append(poolIndices, idx)
+		}
+
+		if len(poolIndices) > 0 && globalEndpoints[poolIndices[0]].Endpoints[0].IsLocal {
+			go func() {
 				r := rand.New(rand.NewSource(time.Now().UnixNano()))
 				for {
-						if err := z.Decommission(ctx, pool.ID); err != nil {
+					if err := z.Decommission(ctx, poolIndices...); err != nil {
 						if errors.Is(err, errDecommissionAlreadyRunning) {
 							// A previous decommission running found restart it.
+							for _, idx := range poolIndices {
 								z.doDecommissionInRoutine(ctx, idx)
+							}
 							return
 						}
 						if configRetriableErrors(err) {
-								logger.LogIf(ctx, fmt.Errorf("Unable to resume decommission of pool %v: %w: retrying..", pool, err))
+							logger.LogIf(ctx, fmt.Errorf("Unable to resume decommission of pools %v: %w: retrying..", pools, err))
 							time.Sleep(time.Second + time.Duration(r.Float64()*float64(5*time.Second)))
 							continue
 						}
-							logger.LogIf(ctx, fmt.Errorf("Unable to resume decommission of pool %v: %w", pool, err))
+						logger.LogIf(ctx, fmt.Errorf("Unable to resume decommission of pool %v: %w", pools, err))
 						return
 					}
-						break
-					}
-				}(pool)
 				}
+			}()
 		}
 
 		return nil
@@ -1039,11 +1023,12 @@ func (z *erasureServerPools) doDecommissionInRoutine(ctx context.Context, idx in
 	}
 
 	z.poolMetaMutex.Lock()
-	failed := z.poolMeta.Pools[idx].Decommission.ItemsDecommissionFailed > 0
+	failed := z.poolMeta.Pools[idx].Decommission.ItemsDecommissionFailed > 0 || contextCanceled(dctx)
+	poolCmdLine := z.poolMeta.Pools[idx].CmdLine
 	z.poolMetaMutex.Unlock()
 
 	if !failed {
-		logger.Info("Decommissioning almost complete - checking for left over objects")
+		logger.Info("Decommissioning complete for pool '%s', verifying for any pending objects", poolCmdLine)
 		err := z.checkAfterDecom(dctx, idx)
 		if err != nil {
 			logger.LogIf(ctx, err)
@@ -1067,8 +1052,8 @@ func (z *erasureServerPools) IsSuspended(idx int) bool {
 }
 
 // Decommission - start decommission session.
-func (z *erasureServerPools) Decommission(ctx context.Context, idx int) error {
-	if idx < 0 {
+func (z *erasureServerPools) Decommission(ctx context.Context, indices ...int) error {
+	if len(indices) == 0 {
 		return errInvalidArgument
 	}
 
@@ -1077,11 +1062,15 @@ func (z *erasureServerPools) Decommission(ctx context.Context, idx int) error {
 	}
 
 	// Make pool unwritable before decommissioning.
-	if err := z.StartDecommission(ctx, idx); err != nil {
+	if err := z.StartDecommission(ctx, indices...); err != nil {
 		return err
 	}
 
-	go z.doDecommissionInRoutine(ctx, idx)
+	go func() {
+		for _, idx := range indices {
+			z.doDecommissionInRoutine(ctx, idx)
+		}
+	}()
 
 	// Successfully started decommissioning.
 	return nil
@@ -1260,8 +1249,8 @@ func (z *erasureServerPools) getBucketsToDecommission(ctx context.Context) ([]de
 	return decomBuckets, nil
 }
 
-func (z *erasureServerPools) StartDecommission(ctx context.Context, idx int) (err error) {
-	if idx < 0 {
+func (z *erasureServerPools) StartDecommission(ctx context.Context, indices ...int) (err error) {
+	if len(indices) == 0 {
 		return errInvalidArgument
 	}
 
@@ -1304,34 +1293,28 @@ func (z *erasureServerPools) StartDecommission(ctx context.Context, idx int) (er
 		}
 	}
 
-	var pool *erasureSets
-	for pidx := range z.serverPools {
-		if pidx == idx {
-			pool = z.serverPools[idx]
-			break
-		}
-	}
-
-	if pool == nil {
-		return errInvalidArgument
-	}
+	z.poolMetaMutex.Lock()
+	defer z.poolMetaMutex.Unlock()
 
+	for _, idx := range indices {
 		pi, err := z.getDecommissionPoolSpaceInfo(idx)
 		if err != nil {
 			return err
 		}
 
-	z.poolMetaMutex.Lock()
-	defer z.poolMetaMutex.Unlock()
-
 		if err = z.poolMeta.Decommission(idx, pi); err != nil {
 			return err
 		}
+
 		z.poolMeta.QueueBuckets(idx, decomBuckets)
+	}
+
 	if err = z.poolMeta.save(ctx, z.serverPools); err != nil {
 		return err
 	}
+
 	globalNotificationSys.ReloadPoolMeta(ctx)
+
 	return nil
 }