Fix L0/L1 stall test (#1201)

The test `TestL0Stall` and `TestL1Stall` would never fail
because of errors in the manifest file. This commit fixes it.

(cherry picked from commit 0acb3f6)

levels.go

@@ -44,12 +44,9 @@ type levelsController struct {
 	kv     *DB
 
 	cstatus compactStatus
-}
-
-var (
 	// This is for getting timings between stalls.
 	lastUnstalled time.Time
-)
+}
 
 // revertToManifest checks that all necessary table files exist and removes all table files not
 // referenced by the manifest. idMap is a set of table file id's that were read from the directory
@@ -929,7 +926,7 @@ func (s *levelsController) addLevel0Table(t *table.Table) error {
 		// Stall. Make sure all levels are healthy before we unstall.
 		var timeStart time.Time
 		{
-			s.elog.Printf("STALLED STALLED STALLED: %v\n", time.Since(lastUnstalled))
+			s.elog.Printf("STALLED STALLED STALLED: %v\n", time.Since(s.lastUnstalled))
 			s.cstatus.RLock()
 			for i := 0; i < s.kv.opt.MaxLevels; i++ {
 				s.elog.Printf("level=%d. Status=%s Size=%d\n",
@@ -956,7 +953,7 @@ func (s *levelsController) addLevel0Table(t *table.Table) error {
 		}
 		{
 			s.elog.Printf("UNSTALLED UNSTALLED UNSTALLED: %v\n", time.Since(timeStart))
-			lastUnstalled = time.Now()
+			s.lastUnstalled = time.Now()
 		}
 	}
 

levels_test.go

@@ -468,7 +468,7 @@ func TestL1Stall(t *testing.T) {
 		db.lc.levels[1].totalSize = 100
 		go func() {
 			tab := createEmptyTable(db)
-			db.lc.addLevel0Table(tab)
+			require.NoError(t, db.lc.addLevel0Table(tab))
 			tab.DecrRef()
 			done <- true
 		}()
@@ -499,24 +499,12 @@ func createEmptyTable(db *DB) *table.Table {
 	b := table.NewTableBuilder(opts)
 	// Add one key so that we can open this table.
 	b.Add(y.KeyWithTs([]byte("foo"), 1), y.ValueStruct{}, 0)
-	fd, err := y.CreateSyncedFile(table.NewFilename(db.lc.reserveFileID(), db.opt.Dir), true)
-	if err != nil {
-		panic(err)
-	}
 
-	if _, err := fd.Write(b.Finish()); err != nil {
-		panic(err)
-	}
-	tab, err := table.OpenTable(fd, table.Options{})
+	// Open table in memory to avoid adding changes to manifest file.
+	tab, err := table.OpenInMemoryTable(b.Finish(), db.lc.reserveFileID(), &opts)
 	if err != nil {
 		panic(err)
 	}
-	// Add dummy entry to manifest file so that it doesn't complain during compaction.
-	if err := db.manifest.addChanges([]*pb.ManifestChange{
-		newCreateChange(tab.ID(), 0, 0, tab.CompressionType()),
-	}); err != nil {
-		panic(err)
-	}
 
 	return tab
 }
@@ -537,7 +525,7 @@ func TestL0Stall(t *testing.T) {
 
 			go func() {
 				tab := createEmptyTable(db)
-				db.lc.addLevel0Table(tab)
+				require.NoError(t, db.lc.addLevel0Table(tab))
 				tab.DecrRef()
 				done <- true
 			}()