Files
seaweedfs/weed/server/master_grpc_server_assign_test.go
Chris LuandGitHub 6206f60032 fix(master): let the growth initiator wait instead of shedding itself (#10202)
* fix(master): let the growth initiator wait for the growth it triggered

The growth-in-flight shed also fired on the request that initiated the
growth: it sets the pending flag right before the shed check, so a
cold-start assign enqueued growth and immediately failed itself with
"volume growth in progress". With no concurrent assigns around to pick
up the freshly grown volume, a single writer against an empty cluster
never completes a write despite ample free space.

Claim the pending flag with a compare-and-swap so exactly one request
becomes the initiator, triggering growth at most once, and let it wait
for that growth to land. Everyone else still sheds retryably instead of
pinning a goroutine: followers behind an in-flight growth, an initiator
whose growth concluded without yielding a writable volume, and an
initiator whose growth outlives the 10s wait budget, which previously
surfaced a non-retryable error (gRPC Unknown, HTTP 406) even though a
retry would have succeeded moments later.

* fix(master): stop assign waits when the request is cancelled

The assign retry loops slept through client cancellation, keeping a
goroutine spinning for the rest of the 10s budget after the caller had
gone; StreamAssign also ran assigns on a background context detached
from the stream. Wait on the request context and pass the stream
context through.

* topology: drop the unconditional grow-request setter

Growth is only claimed through AddGrowRequestIfAbsent's compare-and-swap
now; keeping the raw Store(true) around invites the check-then-set race
back.

* test: cover cold-start first write with a real cluster

Boot a fresh master plus three empty volume servers and require the very
first assign - HTTP and gRPC, each on a cold volume layout, no client
retries - to complete a write. The assign that triggers volume growth
must wait for it rather than answering "volume growth in progress";
unit tests stub the topology, so only a real cluster exercises the
assign-grow-wait path end to end.
2026-07-02 15:13:46 -07:00

194 lines
7.0 KiB
Go

package weed_server
import (
"context"
"testing"
"time"
"github.com/seaweedfs/raft"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
"github.com/seaweedfs/seaweedfs/weed/security"
"github.com/seaweedfs/seaweedfs/weed/sequence"
"github.com/seaweedfs/seaweedfs/weed/storage"
"github.com/seaweedfs/seaweedfs/weed/storage/needle"
"github.com/seaweedfs/seaweedfs/weed/storage/super_block"
"github.com/seaweedfs/seaweedfs/weed/storage/types"
"github.com/seaweedfs/seaweedfs/weed/topology"
)
// leaderRaftServer answers only State(); the embedded nil interface panics if any
// other method is called.
type leaderRaftServer struct {
raft.Server
}
func (leaderRaftServer) State() string { return raft.Leader }
func newLeaderMaster() *MasterServer {
topo := topology.NewTopology("test", sequence.NewMemorySequencer(), 1<<20, 5, false)
topo.RaftServer = leaderRaftServer{}
return &MasterServer{
Topo: topo,
option: &MasterOption{},
guard: security.NewGuard(nil, "", 0, "", 0),
volumeGrowthRequestChan: make(chan *topology.VolumeGrowRequest, 1<<6),
}
}
// markGrowthInFlight flags growth on the same VolumeLayout the handler resolves,
// by mirroring its exact lookup.
func markGrowthInFlight(t *testing.T, topo *topology.Topology, req *master_pb.AssignRequest) {
t.Helper()
rp, err := super_block.NewReplicaPlacementFromString(req.Replication)
require.NoError(t, err)
ttl, err := needle.ReadTTL(req.Ttl)
require.NoError(t, err)
topo.GetVolumeLayout(req.Collection, rp, ttl, types.ToDiskType(req.DiskType)).AddGrowRequestIfAbsent()
}
// With free space but no writable volume and growth already in flight, Assign
// sheds with a retryable ResourceExhausted immediately instead of spinning to
// timeout. ResourceExhausted (not Unavailable) so the shed isn't mistaken for a
// dead channel and doesn't tear down the shared master connection.
func TestAssignShedsLoadWhenGrowthInFlight(t *testing.T) {
ms := newLeaderMaster()
// Free volume slots but no writable volume yet, so growth is the remedy.
ms.Topo.GetOrCreateDataCenter("dc1").GetOrCreateRack("rack1").
GetOrCreateDataNode("127.0.0.1", 8080, 18080, "127.0.0.1", "dn1", map[string]uint32{"": 100})
req := &master_pb.AssignRequest{Count: 1, Replication: "000"}
markGrowthInFlight(t, ms.Topo, req)
start := time.Now()
resp, err := ms.Assign(context.Background(), req)
elapsed := time.Since(start)
require.Error(t, err)
require.Nil(t, resp)
st, ok := status.FromError(err)
require.True(t, ok)
assert.Equal(t, codes.ResourceExhausted, st.Code())
// Shed immediately rather than spinning out the 10s retry budget.
assert.Less(t, elapsed, 2*time.Second)
// Growth was already pending, so we must not enqueue another grow request.
assert.Len(t, ms.volumeGrowthRequestChan, 0)
}
// The assign that triggers growth must not shed itself: on a cold cluster there
// is no other request to pick up the volume, so it waits for the growth it
// started and returns the fresh volume once it lands.
func TestAssignInitiatorWaitsForItsOwnGrowth(t *testing.T) {
ms := newLeaderMaster()
dn := ms.Topo.GetOrCreateDataCenter("dc1").GetOrCreateRack("rack1").
GetOrCreateDataNode("127.0.0.1", 8080, 18080, "127.0.0.1", "dn1", map[string]uint32{"": 100})
req := &master_pb.AssignRequest{Count: 1, Replication: "000"}
rp, err := super_block.NewReplicaPlacementFromString(req.Replication)
require.NoError(t, err)
// Simulate growth landing shortly after it is requested by registering a
// writable volume, then draining the request the initiator enqueued.
go func() {
req := <-ms.volumeGrowthRequestChan
v := storage.VolumeInfo{
Id: needle.VolumeId(1),
Version: needle.GetCurrentVersion(),
ReplicaPlacement: rp,
Ttl: needle.EMPTY_TTL,
}
dn.UpdateVolumes([]storage.VolumeInfo{v})
ms.Topo.RegisterVolumeLayout(v, dn)
ms.Topo.GetVolumeLayout(req.Option.Collection, rp, needle.EMPTY_TTL, types.ToDiskType("")).DoneGrowRequest()
}()
start := time.Now()
resp, err := ms.Assign(context.Background(), req)
elapsed := time.Since(start)
require.NoError(t, err)
require.NotNil(t, resp)
assert.NotEmpty(t, resp.Fid)
// It waited for growth rather than shedding, but well inside the retry budget.
assert.Less(t, elapsed, 5*time.Second)
}
// An initiator whose growth concludes without yielding a writable volume
// (failed or discarded growth) sheds retryably instead of re-triggering
// growth for the rest of its budget.
func TestAssignInitiatorShedsWhenGrowthConcludesUnfulfilled(t *testing.T) {
ms := newLeaderMaster()
ms.Topo.GetOrCreateDataCenter("dc1").GetOrCreateRack("rack1").
GetOrCreateDataNode("127.0.0.1", 8080, 18080, "127.0.0.1", "dn1", map[string]uint32{"": 100})
req := &master_pb.AssignRequest{Count: 1, Replication: "000"}
rp, err := super_block.NewReplicaPlacementFromString(req.Replication)
require.NoError(t, err)
vl := ms.Topo.GetVolumeLayout("", rp, needle.EMPTY_TTL, types.ToDiskType(""))
// Growth consumer that fails: clears the flag without registering volumes.
go func() {
<-ms.volumeGrowthRequestChan
vl.DoneGrowRequest()
}()
start := time.Now()
resp, err := ms.Assign(context.Background(), req)
elapsed := time.Since(start)
require.Error(t, err)
require.Nil(t, resp)
st, ok := status.FromError(err)
require.True(t, ok)
assert.Equal(t, codes.ResourceExhausted, st.Code())
assert.Less(t, elapsed, 2*time.Second)
// Growth was triggered exactly once, not re-enqueued after the failure.
assert.Len(t, ms.volumeGrowthRequestChan, 0)
}
// A cancelled request stops waiting instead of sleeping out the 10s budget.
func TestAssignAbortsOnCancel(t *testing.T) {
ms := newLeaderMaster()
ms.Topo.GetOrCreateDataCenter("dc1").GetOrCreateRack("rack1").
GetOrCreateDataNode("127.0.0.1", 8080, 18080, "127.0.0.1", "dn1", map[string]uint32{"": 100})
// Initiator with its growth never concluding: nobody drains the chan.
req := &master_pb.AssignRequest{Count: 1, Replication: "000"}
ctx, cancel := context.WithCancel(context.Background())
go func() {
time.Sleep(300 * time.Millisecond)
cancel()
}()
start := time.Now()
_, err := ms.Assign(ctx, req)
elapsed := time.Since(start)
require.ErrorIs(t, err, context.Canceled)
assert.Less(t, elapsed, 2*time.Second)
}
// Out of space, Assign fails fast with the real error rather than masking it as
// a retryable "growth in progress".
func TestAssignFailsFastWhenOutOfSpace(t *testing.T) {
ms := newLeaderMaster() // no data nodes -> no free space
req := &master_pb.AssignRequest{Count: 1, Replication: "000"}
start := time.Now()
resp, err := ms.Assign(context.Background(), req)
elapsed := time.Since(start)
require.Error(t, err)
require.Nil(t, resp)
if st, ok := status.FromError(err); ok {
assert.NotEqual(t, codes.Unavailable, st.Code())
}
assert.Contains(t, err.Error(), "no free volumes left")
assert.Less(t, elapsed, 2*time.Second)
}