From a1210d1e8d923aa2415a2f3aa91643b7e1686091 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Fri, 19 Feb 2021 03:56:27 -0800
Subject: [PATCH] Revert "volume: avoid file.stat(), file.seek() if possible
 during writes"

This reverts commit c78409a5983145784d128c86541c6715dad3a937.
---
 weed/storage/backend/disk_file.go | 23 ++---------------------
 weed/storage/needle_map.go        | 16 ++++------------
 2 files changed, 6 insertions(+), 33 deletions(-)

diff --git a/weed/storage/backend/disk_file.go b/weed/storage/backend/disk_file.go
index 6a42ad8e7..2b04c8df2 100644
--- a/weed/storage/backend/disk_file.go
+++ b/weed/storage/backend/disk_file.go
@@ -12,8 +12,6 @@ var (
 type DiskFile struct {
 	File         *os.File
 	fullFilePath string
-	fileSize     int64
-	modTime      time.Time
 }
 
 func NewDiskFile(f *os.File) *DiskFile {
@@ -28,24 +26,11 @@ func (df *DiskFile) ReadAt(p []byte, off int64) (n int, err error) {
 }
 
 func (df *DiskFile) WriteAt(p []byte, off int64) (n int, err error) {
-	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
+	return df.File.WriteAt(p, off)
 }
 
 func (df *DiskFile) Truncate(off int64) error {
-	err := df.File.Truncate(off)
-	if err == nil {
-		df.fileSize = off
-		df.modTime = time.Now()
-	}
-	return err
+	return df.File.Truncate(off)
 }
 
 func (df *DiskFile) Close() error {
@@ -53,9 +38,6 @@ 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
@@ -68,6 +50,5 @@ func (df *DiskFile) Name() string {
 }
 
 func (df *DiskFile) Sync() error {
-	df.fileSize = 0
 	return df.File.Sync()
 }
diff --git a/weed/storage/needle_map.go b/weed/storage/needle_map.go
index f12198c57..5b41286ea 100644
--- a/weed/storage/needle_map.go
+++ b/weed/storage/needle_map.go
@@ -41,7 +41,6 @@ type baseNeedleMapper struct {
 
 	indexFile           *os.File
 	indexFileAccessLock sync.Mutex
-	indexFileOffset     int64
 }
 
 func (nm *baseNeedleMapper) IndexFileSize() uint64 {
@@ -57,18 +56,11 @@ func (nm *baseNeedleMapper) appendToIndexFile(key NeedleId, offset Offset, size
 
 	nm.indexFileAccessLock.Lock()
 	defer nm.indexFileAccessLock.Unlock()
-	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)
+	if _, err := nm.indexFile.Seek(0, 2); err != nil {
+		return fmt.Errorf("cannot seek end of indexfile %s: %v",
+			nm.indexFile.Name(), err)
 	}
+	_, err := nm.indexFile.Write(bytes)
 	return err
 }