Files
seaweedfs/test/master_cold_start/assign_test.go
T
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

120 lines
3.5 KiB
Go

package master_cold_start
import (
"bytes"
"context"
"encoding/json"
"fmt"
"io"
"mime/multipart"
"net/http"
"testing"
"time"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials/insecure"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
)
// The very first write against a fresh cluster must succeed in one shot: the
// assign that triggers volume growth waits for it instead of shedding itself
// with "volume growth in progress". No client retries — a single request per
// assign, like a plain HTTP client.
func TestColdStartFirstWrite(t *testing.T) {
c := StartCluster(t, 3)
// Each subtest uses its own replication so its volume layout starts cold.
t.Run("http_assign_and_write", func(t *testing.T) {
client := &http.Client{Timeout: 15 * time.Second}
resp, err := client.Get(c.MasterURL() + "/dir/assign?replication=002")
if err != nil {
t.Fatalf("dir/assign: %v", err)
}
body, _ := io.ReadAll(resp.Body)
resp.Body.Close()
if resp.StatusCode != http.StatusOK {
t.Fatalf("dir/assign returned %d: %s", resp.StatusCode, body)
}
var assign struct {
Fid string `json:"fid"`
Url string `json:"url"`
Error string `json:"error"`
}
if err := json.Unmarshal(body, &assign); err != nil {
t.Fatalf("parse assign response %q: %v", body, err)
}
if assign.Error != "" || assign.Fid == "" {
t.Fatalf("assign failed: %s", body)
}
content := []byte("cold start write")
if err := uploadAndReadBack(client, assign.Url, assign.Fid, content); err != nil {
t.Fatal(err)
}
})
t.Run("grpc_assign", func(t *testing.T) {
grpcDialOption := grpc.WithTransportCredentials(insecure.NewCredentials())
err := pb.WithMasterClient(context.Background(), false, pb.ServerAddress(c.MasterAddress()), grpcDialOption, false,
func(client master_pb.SeaweedClient) error {
ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
defer cancel()
resp, err := client.Assign(ctx, &master_pb.AssignRequest{Count: 1, Replication: "001"})
if err != nil {
return err
}
if resp.Error != "" || resp.Fid == "" {
return fmt.Errorf("assign failed: %+v", resp)
}
return nil
})
if err != nil {
t.Fatalf("single grpc assign on cold cluster: %v", err)
}
})
}
// uploadAndReadBack writes content to the assigned fid and reads it back.
func uploadAndReadBack(client *http.Client, volumeUrl, fid string, content []byte) error {
var buf bytes.Buffer
writer := multipart.NewWriter(&buf)
part, err := writer.CreateFormFile("file", "cold_start.txt")
if err != nil {
return err
}
part.Write(content)
writer.Close()
target := fmt.Sprintf("http://%s/%s", volumeUrl, fid)
req, err := http.NewRequest(http.MethodPost, target, &buf)
if err != nil {
return err
}
req.Header.Set("Content-Type", writer.FormDataContentType())
resp, err := client.Do(req)
if err != nil {
return fmt.Errorf("upload to %s: %w", target, err)
}
body, _ := io.ReadAll(resp.Body)
resp.Body.Close()
if resp.StatusCode != http.StatusCreated && resp.StatusCode != http.StatusOK {
return fmt.Errorf("upload to %s returned %d: %s", target, resp.StatusCode, body)
}
resp, err = client.Get(target)
if err != nil {
return fmt.Errorf("read back %s: %w", target, err)
}
got, _ := io.ReadAll(resp.Body)
resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return fmt.Errorf("read back %s returned %d", target, resp.StatusCode)
}
if !bytes.Equal(got, content) {
return fmt.Errorf("read back %s: got %q, want %q", target, got, content)
}
return nil
}