Files
seaweedfs/weed/server/master_grpc_server_volume.go
T
Chris LuandDevin 5e01caa522 master: cap parallel vacuums per rack via master.vacuum.max_parallel_per_rack (#11935)
* master: cap parallel vacuums per rack via -maxParallelVacuumPerRack

Hosts that run one volume server per disk under a single rack label could
not bound host-level vacuum I/O: maxParallelVacuumPerServer limits each
process, so every disk on the machine compacted at once. A second quota
map keyed on rack id debits alongside the per-server one, so at most N
volume copies compact in parallel within a rack. Defaults to 0 (no
limit); the flag is wired on master, server, mini and master.follower.

* master: resolve a data node's rack key once per vacuum sweep

A volume server that unregisters mid-sweep loses its parent node, so the
quota credit path calling dn.GetRack() panicked and crashed the master.
Rack names are also local to their data center, so same-named racks in
different centers shared one quota bucket. Each node's rack key is now
captured when the limiters are built and carries the data center id, so
checks, debits and credits never touch the live parent pointer.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* master: reserve vacuum quota per needed copy count, not per copy

Each copy of a volume checked the shared server/rack quota independently,
so several same-rack replicas all passed against one remaining slot and
the debits drove the bucket negative. Needs are now counted per server
and per rack first; a volume whose own copies exceed a cap reserves the
whole bucket once it is free instead of pending forever.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* master.follower: register -maxParallelVacuumPerRack as a flag

It was only a fixed default, so passing the flag on the command line
failed flag parsing.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* master: key the rack vacuum quota by rack node identity

Joining data center and rack names with "/" still let two different racks
share one bucket when the names themselves contained slashes. Key the
limiter by the rack node instead, which is unique per rack regardless of
naming.

* master: keep the tiered-replica vacuum test through the rebase

* master: document 0 as no limit for -maxParallelVacuumPerServer

The clamped per-server need makes a non-positive cap mean "no limit",
matching the new rack flag; say so in the flag help.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* master: key the rack-key cache by data node identity

Node ids are only unique within a rack, so two servers that share an id
in different racks would have reused the first server's cached rack and
escaped the per-rack vacuum cap.

* master: read the per-rack vacuum cap from master.toml

-maxParallelVacuumPerRack becomes the master.max_parallel_vacuum_per_rack
config key, so the new master limit is set the same way as other master
options instead of a flag wired into every command that embeds a master.

* master: let master.max_parallel_vacuum_per_server override the flag

The released -maxParallelVacuumPerServer flag keeps working, but a value
in master.toml now wins when set, matching how master.mdir already
overrides -mdir.

* master: group the vacuum caps under master.vacuum in master.toml

Rename master.max_parallel_vacuum_per_rack to master.vacuum.max_parallel_per_rack
and master.max_parallel_vacuum_per_server to master.vacuum.max_parallel_per_server,
so the keys sit in one subsystem table like master.volume_growth and
master.maintenance.

* master: deprecate -maxParallelVacuumPerServer for master.toml

The flag still works - and is overridden by
master.vacuum.max_parallel_per_server when set - but the help text now
points operators at the config key, matching the codebase style of
help-text-only deprecation.

* topology: read node parent atomically

UnlinkChildNode clears a data node's parent under the rack's lock while
readers like the vacuum sweep's rack capture reach it with no shared
lock, so a torn interface read could crash the master. Store the parent
in an atomic.Pointer and nil-guard the detached walk in
DataNode.GetTopology.

---------

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
2026-10-23 22:41:36 -07:00

553 lines
19 KiB
Go

package weed_server
import (
"context"
"fmt"
"math/rand/v2"
"strings"
"sync"
"time"
"github.com/seaweedfs/seaweedfs/weed/stats"
"github.com/seaweedfs/seaweedfs/weed/topology"
"github.com/seaweedfs/raft"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
"github.com/seaweedfs/seaweedfs/weed/security"
"github.com/seaweedfs/seaweedfs/weed/storage/needle"
"github.com/seaweedfs/seaweedfs/weed/storage/super_block"
"github.com/seaweedfs/seaweedfs/weed/storage/types"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
)
const (
volumeGrowStepCount = 2
)
func (ms *MasterServer) DoAutomaticVolumeGrow(req *topology.VolumeGrowRequest) {
if ms.option.VolumeGrowthDisabled {
glog.V(1).Infof("automatic volume grow disabled")
return
}
glog.V(1).Infoln("starting automatic volume grow")
start := time.Now()
newVidLocations, err := ms.vg.AutomaticGrowByType(req.Option, ms.grpcDialOption, ms.Topo, req.Count)
glog.V(1).Infoln("finished automatic volume grow, cost ", time.Now().Sub(start))
if err != nil {
glog.V(1).Infof("automatic volume grow failed: %+v", err)
return
}
ms.broadcastVolumeLocationsToClients(newVidLocations)
}
// periodicGrowCount decides how many volumes the periodic growth scan adds to
// a layout ahead of its rack-aware pass, from the writableVolumeCount clients
// last asked for (lastGrowCount) and the layout's writable and crowded counts.
// mustGrow reports a refill back up to lastGrowCount writable volumes, which
// the caller only grows when there is room for all of it. A layout that never
// received a writableVolumeCount (lastGrowCount 0) is left to the rack-aware
// pass.
func periodicGrowCount(lastGrowCount uint32, writable, crowded int) (count uint32, mustGrow bool) {
if n := int(lastGrowCount) - writable; n > 0 {
return uint32(n), true
}
if lastGrowCount > 0 && writable < int(lastGrowCount*2) && float64(crowded+volumeGrowStepCount) > float64(writable)*topology.VolumeGrowStrategy.Threshold {
return volumeGrowStepCount, false
}
return 0, false
}
func (ms *MasterServer) ProcessGrowRequest() {
go func() {
ctx := context.Background()
firstRun := true
for {
if firstRun {
firstRun = false
} else {
time.Sleep(5*time.Minute + time.Duration(30*rand.Float32())*time.Second)
}
if !ms.Topo.IsLeader() {
continue
}
dcs := ms.Topo.ListDCAndRacks()
for _, vlc := range ms.Topo.ListVolumeLayoutCollections() {
var err error
vl := vlc.VolumeLayout
lastGrowCount := vl.GetLastGrowCount()
if vl.HasGrowRequest() {
continue
}
writable, crowded := vl.GetWritableVolumeCount()
vgr := vlc.ToVolumeGrowRequest()
underReplicated := vl.CountUnderReplicatedVolumes()
stats.MasterVolumeLayoutWritable.WithLabelValues(vlc.Collection, vgr.DiskType, vgr.Replication, vgr.Ttl).Set(float64(writable))
stats.MasterVolumeLayoutCrowded.WithLabelValues(vlc.Collection, vgr.DiskType, vgr.Replication, vgr.Ttl).Set(float64(crowded))
stats.MasterUnderReplicatedVolumes.WithLabelValues(vlc.Collection, vgr.DiskType, vgr.Replication, vgr.Ttl).Set(float64(underReplicated))
growCount, mustGrow := periodicGrowCount(lastGrowCount, writable, crowded)
switch {
case mustGrow:
if rp, rpErr := super_block.NewReplicaPlacementFromString(vgr.Replication); rpErr != nil {
glog.V(0).Infof("failed to parse replica placement %s: %v", vgr.Replication, rpErr)
} else {
vgr.WritableVolumeCount = growCount
if ms.Topo.AvailableSpaceFor(&topology.VolumeGrowOption{DiskType: types.ToDiskType(vgr.DiskType)}) >= int64(vgr.WritableVolumeCount*uint32(rp.GetCopyCount())) {
_, err = ms.VolumeGrow(ctx, vgr)
}
}
case growCount > 0:
vgr.WritableVolumeCount = growCount
_, err = ms.VolumeGrow(ctx, vgr)
}
if err != nil {
glog.V(0).Infof("volume grow request failed: %+v", err)
}
for _, plan := range vl.PlanRackAwareGrowth(dcs, lastGrowCount, volumeGrowStepCount) {
vgr.DataCenter = plan.DataCenter
vgr.Rack = plan.Rack
vgr.WritableVolumeCount = plan.WritableVolumeCount
if _, err = ms.VolumeGrow(ctx, vgr); err != nil {
glog.V(0).Infof("volume grow request for dc:%s rack:%s failed: %+v", plan.DataCenter, plan.Rack, err)
}
}
}
}
}()
go func() {
filter := sync.Map{}
for {
req, ok := <-ms.volumeGrowthRequestChan
if !ok {
break
}
option := req.Option
vl := ms.Topo.GetVolumeLayout(option.Collection, option.ReplicaPlacement, option.Ttl, option.DiskType)
if !ms.Topo.IsLeader() {
//discard buffered requests
time.Sleep(time.Second * 1)
vl.DoneGrowRequest()
continue
}
// filter out identical requests being processed
found := false
filter.Range(func(k, v interface{}) bool {
existingReq := k.(*topology.VolumeGrowRequest)
if existingReq.Equals(req) {
found = true
}
return !found
})
// not atomic but it's okay
if found || (!req.Force && !vl.ShouldGrowVolumes()) {
glog.V(4).Infoln("discard volume grow request")
time.Sleep(time.Millisecond * 211)
vl.DoneGrowRequest()
continue
}
filter.Store(req, nil)
// we have lock called inside vg
glog.V(0).Infof("volume grow %+v", req)
go func(req *topology.VolumeGrowRequest, vl *topology.VolumeLayout) {
// defer so a panic can't strand growRequest.
defer filter.Delete(req)
defer vl.DoneGrowRequest()
ms.DoAutomaticVolumeGrow(req)
}(req, vl)
}
}()
}
// LookupVolume resolves one or more volume ids (or "<vid>,<cookie>" file ids)
// to their current replica locations on the volume servers. Each returned
// entry carries DataInRemote per replica so the caller can prefer a local
// replica; entries carrying a file id also receive a freshly generated read
// jwt the volume server will accept.
func (ms *MasterServer) LookupVolume(ctx context.Context, req *master_pb.LookupVolumeRequest) (*master_pb.LookupVolumeResponse, error) {
resp := &master_pb.LookupVolumeResponse{}
volumeLocations := ms.lookupVolumeId(req.VolumeOrFileIds, req.Collection)
notFoundCount := 0
for _, volumeOrFileId := range req.VolumeOrFileIds {
vid := volumeOrFileId
commaSep := strings.Index(vid, ",")
if commaSep > 0 {
vid = vid[0:commaSep]
}
if result, found := volumeLocations[vid]; found {
var locations []*master_pb.Location
for _, loc := range result.Locations {
locations = append(locations, &master_pb.Location{
Url: loc.Url,
PublicUrl: loc.PublicUrl,
DataCenter: loc.DataCenter,
GrpcPort: uint32(loc.GrpcPort),
DataInRemote: loc.DataInRemote,
ReadOnly: loc.ReadOnly,
ReadOnlyCanDelete: loc.ReadOnlyCanDelete,
})
}
var auth string
if commaSep > 0 { // this is a file id
auth = string(security.GenJwtForVolumeServer(ms.guard.SigningKey(), ms.guard.ExpiresAfterSec(), result.VolumeOrFileId))
}
if result.NotFound {
notFoundCount++
}
resp.VolumeIdLocations = append(resp.VolumeIdLocations, &master_pb.LookupVolumeResponse_VolumeIdLocation{
VolumeOrFileId: result.VolumeOrFileId,
Locations: locations,
Error: result.Error,
Auth: auth,
})
}
}
// While warming up, a not-found may only mean the volume server has not
// reported yet, so no part of the answer can be treated as authoritative.
// Callers retry Unavailable; a partial answer would let them take a
// missing volume as gone.
if notFoundCount > 0 && ms.Topo.IsLeader() && ms.Topo.IsWarmingUp() {
glog.V(0).Infof("lookup volume warming up: topology is still loading (%d of %d not found)", notFoundCount, len(req.VolumeOrFileIds))
return nil, status.Errorf(codes.Unavailable, "master is warming up, topology is still loading")
}
return resp, nil
}
// CollectionStatistics summarises every collection, so callers tracking usage
// do not pull the whole volume list to add it up themselves.
func (ms *MasterServer) CollectionStatistics(ctx context.Context, req *master_pb.CollectionStatisticsRequest) (*master_pb.CollectionStatisticsResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
stats := ms.Topo.CollectionStatistics()
resp := &master_pb.CollectionStatisticsResponse{
Collections: make([]*master_pb.CollectionStatistics, 0, len(stats)),
}
for _, s := range stats {
resp.Collections = append(resp.Collections, &master_pb.CollectionStatistics{
Collection: s.Collection,
FileCount: s.FileCount,
DeleteCount: s.DeleteCount,
DeletedByteCount: s.DeletedByteCount,
Size: s.Size,
PhysicalSize: s.PhysicalSize,
VolumeCount: s.VolumeCount,
})
}
return resp, nil
}
func (ms *MasterServer) Statistics(ctx context.Context, req *master_pb.StatisticsRequest) (*master_pb.StatisticsResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
// an empty collection means all collections, and a named collection covers
// all its layouts and EC volumes
stats := ms.Topo.CollectionVolumeStats(req.Collection)
totalSize := uint64(ms.Topo.GetDiskUsages().GetMaxVolumeCount() * int64(ms.option.VolumeSizeLimitMB) * 1024 * 1024)
// capacity is cluster-wide, so what is left over is what every collection
// has not taken, not just the one asked about
clusterUsedSize := stats.UsedSize
if req.Collection != "" {
clusterUsedSize = ms.Topo.CollectionVolumeStats("").UsedSize
}
// volume slots are provisioning, not capacity: a cluster configured with
// more of them than its disks hold would report space it can never take.
// What the disks still have free, on top of what the cluster already wrote,
// is the real ceiling.
if freeBytes, reported := ms.Topo.FreeBytes(); reported {
totalSize = min(totalSize, clusterUsedSize+freeBytes)
}
// and the free space holds that many copies fewer of whatever the caller writes
var freeSize uint64
if totalSize > clusterUsedSize {
freeSize = (totalSize - clusterUsedSize) / uint64(ms.replicaCopyCount(req.Replication))
}
resp := &master_pb.StatisticsResponse{
TotalSize: totalSize,
UsedSize: stats.UsedSize,
FileCount: stats.FileCount,
LogicalTotalSize: stats.LogicalUsedSize + freeSize,
LogicalUsedSize: stats.LogicalUsedSize,
}
return resp, nil
}
// replicaCopyCount returns how many copies the given replication makes, falling
// back to the master default and then to a single copy. Unparsable input is
// reported rather than failing the call: statistics are informational.
func (ms *MasterServer) replicaCopyCount(replication string) int {
for _, s := range []string{replication, ms.option.DefaultReplicaPlacement} {
if s == "" {
continue
}
rp, err := super_block.NewReplicaPlacementFromString(s)
if err != nil {
glog.V(1).Infof("statistics replication %q: %v", s, err)
continue
}
return rp.GetCopyCount()
}
return 1
}
func (ms *MasterServer) VolumeList(ctx context.Context, req *master_pb.VolumeListRequest) (*master_pb.VolumeListResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
filter, err := topology.NewVolumeFilter(req)
if err != nil {
return nil, status.Error(codes.InvalidArgument, err.Error())
}
resp := &master_pb.VolumeListResponse{
TopologyInfo: ms.Topo.ToTopologyInfo(filter),
VolumeSizeLimitMb: uint64(ms.option.VolumeSizeLimitMB),
}
return resp, nil
}
// VolumeListStream answers VolumeList without building the whole reply first.
// The topology goes out on its own, then the volumes in batches, so the master
// holds one batch rather than every volume in the cluster.
func (ms *MasterServer) VolumeListStream(req *master_pb.VolumeListRequest, stream master_pb.Seaweed_VolumeListStreamServer) error {
if !ms.Topo.IsLeader() {
return raft.NotLeaderError
}
filter, err := topology.NewVolumeFilter(req)
if err != nil {
return status.Error(codes.InvalidArgument, err.Error())
}
listed := ms.Topo.ToTopologyInfo(topology.NoVolumes())
err = stream.Send(&master_pb.VolumeListStreamResponse{
Header: &master_pb.VolumeListResponse{
TopologyInfo: listed,
VolumeSizeLimitMb: uint64(ms.option.VolumeSizeLimitMB),
},
})
if err != nil {
return err
}
return ms.Topo.StreamVolumes(listed, filter, 0, stream.Send)
}
func (ms *MasterServer) LookupEcVolume(ctx context.Context, req *master_pb.LookupEcVolumeRequest) (*master_pb.LookupEcVolumeResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
resp := &master_pb.LookupEcVolumeResponse{}
ecLocations, found := ms.Topo.LookupEcShards(needle.VolumeId(req.VolumeId))
if !found {
return resp, fmt.Errorf("ec volume %d not found", req.VolumeId)
}
resp.VolumeId = req.VolumeId
for shardId, shardLocations := range ecLocations.Locations {
var locations []*master_pb.Location
for _, dn := range shardLocations {
locations = append(locations, &master_pb.Location{
Url: dn.Url(),
PublicUrl: dn.PublicUrl,
DataCenter: dn.GetDataCenterId(),
// without this, clients derive grpc as httpPort+10000
GrpcPort: uint32(dn.GrpcPort),
})
}
resp.ShardIdLocations = append(resp.ShardIdLocations, &master_pb.LookupEcVolumeResponse_EcShardIdLocation{
ShardId: uint32(shardId),
Locations: locations,
})
}
return resp, nil
}
func (ms *MasterServer) VacuumVolume(ctx context.Context, req *master_pb.VacuumVolumeRequest) (*master_pb.VacuumVolumeResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
resp := &master_pb.VacuumVolumeResponse{}
ms.Topo.Vacuum(ms.grpcDialOption, float64(req.GarbageThreshold), ms.option.MaxParallelVacuumPerServer, ms.option.MaxParallelVacuumPerRack, req.VolumeId, req.Collection, ms.preallocateSize, false, 0)
return resp, nil
}
func (ms *MasterServer) DisableVacuum(ctx context.Context, req *master_pb.DisableVacuumRequest) (*master_pb.DisableVacuumResponse, error) {
// The caller explicitly indicates whether this disable request comes
// from the vacuum plugin monitor. Track ownership so the safety net
// in the vacuum loop won't override an operator's intentional disable.
if req.GetByPlugin() {
ms.Topo.DisableVacuumByPlugin()
} else {
ms.Topo.DisableVacuum()
}
resp := &master_pb.DisableVacuumResponse{}
return resp, nil
}
func (ms *MasterServer) EnableVacuum(ctx context.Context, req *master_pb.EnableVacuumRequest) (*master_pb.EnableVacuumResponse, error) {
if req.GetByPlugin() {
ms.Topo.EnableVacuumByPlugin()
} else {
ms.Topo.EnableVacuum()
}
resp := &master_pb.EnableVacuumResponse{}
return resp, nil
}
func (ms *MasterServer) VolumeMarkReadonly(ctx context.Context, req *master_pb.VolumeMarkReadonlyRequest) (*master_pb.VolumeMarkReadonlyResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
resp := &master_pb.VolumeMarkReadonlyResponse{}
replicaPlacement, _ := super_block.NewReplicaPlacementFromByte(byte(req.ReplicaPlacement))
vl := ms.Topo.GetVolumeLayout(req.Collection, replicaPlacement, needle.LoadTTLFromUint32(req.Ttl), types.ToDiskType(req.DiskType))
vid := needle.VolumeId(req.VolumeId)
dataNodes := ms.Topo.Lookup(req.Collection, vid)
found := false
for _, dn := range dataNodes {
if dn.Ip == req.Ip && dn.Port == int(req.Port) {
found = true
if req.IsReadonly {
vl.SetVolumeReadOnly(dn, vid)
if pending := vl.GetPendingSize(vid); pending > 0 {
glog.V(0).Infof("volume %d marked readonly with %d pending bytes", vid, pending)
}
} else {
vl.SetVolumeWritable(dn, vid)
}
}
}
// A vacuum worker marks the volume writable after a successful commit. If the
// index lost it meanwhile (e.g. a disconnect race during the vacuum), the loop
// found nothing to update; re-register it from the node that still holds it so
// LookupVolume stops returning "not found".
if !found && !req.IsReadonly {
if dn := ms.Topo.LookupDataNodeByAddress(pb.NewServerAddress(req.Ip, int(req.Port), 0)); dn != nil {
if vi, err := dn.GetVolumesById(vid); err == nil {
ms.Topo.RegisterVolumeLayout(vi, dn)
glog.V(0).Infof("volume %d re-registered from %s:%d, was missing from the lookup index at mark-writable", vid, req.Ip, req.Port)
}
}
}
return resp, nil
}
func (ms *MasterServer) ResumeVolumeGrowth(ctx context.Context, req *master_pb.ResumeVolumeGrowthRequest) (*master_pb.ResumeVolumeGrowthResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
return &master_pb.ResumeVolumeGrowthResponse{WasFrozen: ms.Topo.ResumeVolumeGrowth()}, nil
}
func (ms *MasterServer) VolumeGrow(ctx context.Context, req *master_pb.VolumeGrowRequest) (*master_pb.VolumeGrowResponse, error) {
if !ms.Topo.IsLeader() {
return nil, raft.NotLeaderError
}
if req.Replication == "" {
req.Replication = ms.option.DefaultReplicaPlacement
}
replicaPlacement, err := super_block.NewReplicaPlacementFromString(req.Replication)
if err != nil {
return nil, err
}
ttl, err := needle.ReadTTL(req.Ttl)
if err != nil {
return nil, err
}
if req.DataCenter != "" && !ms.Topo.DataCenterExists(req.DataCenter) {
return nil, fmt.Errorf("data center not exists")
}
ver := needle.GetCurrentVersion()
volumeGrowOption := topology.VolumeGrowOption{
Collection: req.Collection,
ReplicaPlacement: replicaPlacement,
Ttl: ttl,
DiskType: types.ToDiskType(req.DiskType),
Preallocate: ms.preallocateSize,
DataCenter: req.DataCenter,
Rack: req.Rack,
DataNode: req.DataNode,
MemoryMapMaxSizeMb: req.MemoryMapMaxSizeMb,
Version: uint32(ver),
}
volumeGrowRequest := topology.VolumeGrowRequest{
Option: &volumeGrowOption,
Count: req.WritableVolumeCount,
Force: true,
Reason: "grpc volume grow",
}
// Report the layout's fill observed at request time whether or not
// growth was triggered, so callers can tell an empty layout from a
// skipped one. A missing collection/layout reports zeros.
var avgFill float64
var writableCount int
if vl := ms.Topo.FindVolumeLayout(req.Collection, replicaPlacement, ttl, types.ToDiskType(req.DiskType)); vl != nil {
avgFill, writableCount = vl.WritableAvgFill(&volumeGrowOption)
}
// Conditional grow: with a threshold set, grow only when the layout's
// writable volumes have reached this average fill. A layout with no
// writable volumes (none yet, or all just filled) skips the check — that
// is the case growth exists to fix.
if req.GrowAvgFillThreshold > 0 && writableCount > 0 && avgFill < float64(req.GrowAvgFillThreshold) {
return &master_pb.VolumeGrowResponse{
AvgFill: float32(avgFill),
WritableCount: uint32(writableCount),
}, nil
}
replicaCount := int64(req.WritableVolumeCount * uint32(replicaPlacement.GetCopyCount()))
if ms.Topo.AvailableSpaceFor(&volumeGrowOption) < replicaCount {
return nil, fmt.Errorf("only %d volumes left, not enough for %d", ms.Topo.AvailableSpaceFor(&volumeGrowOption), replicaCount)
}
ms.DoAutomaticVolumeGrow(&volumeGrowRequest)
return &master_pb.VolumeGrowResponse{
AvgFill: float32(avgFill),
WritableCount: uint32(writableCount),
}, nil
}