volume: avoid file.stat(), file.seek() if possible during writes

This commit is contained in:
Chris Lu 2021-02-18 23:22:54 -08:00
parent 29575dadc5
commit c78409a598
2 changed files with 33 additions and 6 deletions

View file

@ -12,6 +12,8 @@ var (
type DiskFile struct {
File *os.File
fullFilePath string
fileSize int64
modTime time.Time
}
func NewDiskFile(f *os.File) *DiskFile {
@ -26,11 +28,24 @@ func (df *DiskFile) ReadAt(p []byte, off int64) (n int, err error) {
}
func (df *DiskFile) WriteAt(p []byte, off int64) (n int, err error) {
return df.File.WriteAt(p, off)
n, err = df.File.WriteAt(p, off)
if err == nil {
waterMark := off + int64(n)
if waterMark > df.fileSize {
df.fileSize = waterMark
df.modTime = time.Now()
}
}
return
}
func (df *DiskFile) Truncate(off int64) error {
return df.File.Truncate(off)
err := df.File.Truncate(off)
if err == nil {
df.fileSize = off
df.modTime = time.Now()
}
return err
}
func (df *DiskFile) Close() error {
@ -38,6 +53,9 @@ func (df *DiskFile) Close() error {
}
func (df *DiskFile) GetStat() (datSize int64, modTime time.Time, err error) {
if df.fileSize != 0 {
return df.fileSize, df.modTime, nil
}
stat, e := df.File.Stat()
if e == nil {
return stat.Size(), stat.ModTime(), nil
@ -50,5 +68,6 @@ func (df *DiskFile) Name() string {
}
func (df *DiskFile) Sync() error {
df.fileSize = 0
return df.File.Sync()
}

View file

@ -41,6 +41,7 @@ type baseNeedleMapper struct {
indexFile *os.File
indexFileAccessLock sync.Mutex
indexFileOffset int64
}
func (nm *baseNeedleMapper) IndexFileSize() uint64 {
@ -56,11 +57,18 @@ func (nm *baseNeedleMapper) appendToIndexFile(key NeedleId, offset Offset, size
nm.indexFileAccessLock.Lock()
defer nm.indexFileAccessLock.Unlock()
if _, err := nm.indexFile.Seek(0, 2); err != nil {
return fmt.Errorf("cannot seek end of indexfile %s: %v",
nm.indexFile.Name(), err)
if nm.indexFileOffset == 0 {
if fileSize, err := nm.indexFile.Seek(0, 2); err != nil {
return fmt.Errorf("cannot seek end of indexfile %s: %v",
nm.indexFile.Name(), err)
} else {
nm.indexFileOffset = fileSize
}
}
written, err := nm.indexFile.WriteAt(bytes, nm.indexFileOffset)
if err == nil {
nm.indexFileOffset += int64(written)
}
_, err := nm.indexFile.Write(bytes)
return err
}