volume: automatically trim out unreachable entries

weed/storage/volume_checking.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/storage/backend"
 	"github.com/chrislusf/seaweedfs/weed/storage/idx"
 	"github.com/chrislusf/seaweedfs/weed/storage/needle"
@@ -11,17 +12,28 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/util"
 )
 
-func CheckVolumeDataIntegrity(v *Volume, indexFile *os.File) (lastAppendAtNs uint64, e error) {
+func CheckAndFixVolumeDataIntegrity(v *Volume, indexFile *os.File) (lastAppendAtNs uint64, err error) {
 	var indexSize int64
-	if indexSize, e = verifyIndexFileIntegrity(indexFile); e != nil {
-		return 0, fmt.Errorf("verifyIndexFileIntegrity %s failed: %v", indexFile.Name(), e)
+	if indexSize, err = verifyIndexFileIntegrity(indexFile); err != nil {
+		return 0, fmt.Errorf("verifyIndexFileIntegrity %s failed: %v", indexFile.Name(), err)
 	}
 	if indexSize == 0 {
 		return 0, nil
 	}
+	for i := 1; i <= 10; i++ {
+		// check and fix last 10 entries
+		lastAppendAtNs, err = doCheckAndFixVolumeData(v, indexFile, indexSize-int64(i)*NeedleMapEntrySize)
+		if err != ErrorSizeMismatch {
+			break
+		}
+	}
+	return
+}
+
+func doCheckAndFixVolumeData(v *Volume, indexFile *os.File, indexOffset int64) (lastAppendAtNs uint64, err error) {
 	var lastIdxEntry []byte
-	if lastIdxEntry, e = readIndexEntryAtOffset(indexFile, indexSize-NeedleMapEntrySize); e != nil {
-		return 0, fmt.Errorf("readLastIndexEntry %s failed: %v", indexFile.Name(), e)
+	if lastIdxEntry, err = readIndexEntryAtOffset(indexFile, indexOffset); err != nil {
+		return 0, fmt.Errorf("readLastIndexEntry %s failed: %v", indexFile.Name(), err)
 	}
 	key, offset, size := idx.IdxFileEntry(lastIdxEntry)
 	if offset.IsZero() {
@@ -29,15 +41,15 @@ func CheckVolumeDataIntegrity(v *Volume, indexFile *os.File) (lastAppendAtNs uin
 	}
 	if size < 0 {
 		// read the deletion entry
-		if lastAppendAtNs, e = verifyDeletedNeedleIntegrity(v.DataBackend, v.Version(), key); e != nil {
-			return lastAppendAtNs, fmt.Errorf("verifyNeedleIntegrity %s failed: %v", indexFile.Name(), e)
+		if lastAppendAtNs, err = verifyDeletedNeedleIntegrity(v.DataBackend, v.Version(), key); err != nil {
+			return lastAppendAtNs, fmt.Errorf("verifyNeedleIntegrity %s failed: %v", indexFile.Name(), err)
 		}
 	} else {
-		if lastAppendAtNs, e = verifyNeedleIntegrity(v.DataBackend, v.Version(), offset.ToAcutalOffset(), key, size); e != nil {
-			return lastAppendAtNs, fmt.Errorf("verifyNeedleIntegrity %s failed: %v", indexFile.Name(), e)
+		if lastAppendAtNs, err = verifyNeedleIntegrity(v.DataBackend, v.Version(), offset.ToAcutalOffset(), key, size); err != nil {
+			return lastAppendAtNs, err
 		}
 	}
-	return
+	return lastAppendAtNs, nil
 }
 
 func verifyIndexFileIntegrity(indexFile *os.File) (indexSize int64, err error) {
@@ -60,18 +72,37 @@ func readIndexEntryAtOffset(indexFile *os.File, offset int64) (bytes []byte, err
 }
 
 func verifyNeedleIntegrity(datFile backend.BackendStorageFile, v needle.Version, offset int64, key NeedleId, size Size) (lastAppendAtNs uint64, err error) {
-	n := new(needle.Needle)
-	// case: node total memory 8g, set volumeLimitSize=2048 , save 10 files, every file size 2.2g or more , when we restart the volume server , while see out of memory error
-	// fix: When the size of the last file exceeds 10M, consider directly returning the last modify time
-	if size > 10 * 1024 * 1024 {
-		bytes , err := needle.ReadNeedleBlob(datFile, offset+int64(size), 0, v);
-		if  err == nil {
-			if v == needle.Version3 {
-				tsOffset := NeedleHeaderSize + 0 + needle.NeedleChecksumSize
-				n.AppendAtNs = util.BytesToUint64(bytes[tsOffset : tsOffset+TimestampSize])
+	n, _, _, err := needle.ReadNeedleHeader(datFile, v, offset)
+	if err != nil {
+		return 0, fmt.Errorf("read %s at %d", datFile.Name(), offset)
+	}
+	if n.Size != size {
+		return 0, ErrorSizeMismatch
+	}
+	if v == needle.Version3 {
+		bytes := make([]byte, TimestampSize)
+		_, err = datFile.ReadAt(bytes, offset+NeedleHeaderSize+int64(size)+needle.NeedleChecksumSize)
+		if err != nil {
+			return 0, fmt.Errorf("check %s entry offset %d size %d: %v", datFile.Name(), offset, size, err)
+		}
+		n.AppendAtNs = util.BytesToUint64(bytes)
+		fileTailOffset := offset + needle.GetActualSize(size, v)
+		fileSize, _, err := datFile.GetStat()
+		if err != nil {
+			return 0, fmt.Errorf("stat file %s: %v", datFile.Name(), err)
+		}
+		if fileSize == fileTailOffset {
+			return n.AppendAtNs, nil
+		}
+		if fileSize > fileTailOffset {
+			glog.Warningf("Truncate %s from %d bytes to %d bytes!", datFile.Name(), fileSize, fileTailOffset)
+			err = datFile.Truncate(fileTailOffset)
+			if err == nil {
+				return n.AppendAtNs, nil
 			}
+			return n.AppendAtNs, fmt.Errorf("truncate file %s: %v", datFile.Name(), err)
 		}
-		return n.AppendAtNs, err
+		glog.Warningf("data file %s has %d bytes, less than expected %d bytes!", datFile.Name(), fileSize, fileTailOffset)
 	}
 	if err = n.ReadData(datFile, offset, size, v); err != nil {
 		return n.AppendAtNs, fmt.Errorf("read data [%d,%d) : %v", offset, offset+int64(size), err)

weed/storage/volume_loading.go

@@ -89,7 +89,7 @@ func (v *Volume) load(alsoLoadIndex bool, createDatIfMissing bool, needleMapKind
 				return fmt.Errorf("cannot write Volume Index %s.idx: %v", fileName, err)
 			}
 		}
-		if v.lastAppendAtNs, err = CheckVolumeDataIntegrity(v, indexFile); err != nil {
+		if v.lastAppendAtNs, err = CheckAndFixVolumeDataIntegrity(v, indexFile); err != nil {
 			v.noWriteOrDelete = true
 			glog.V(0).Infof("volumeDataIntegrityChecking failed %v", err)
 		}