🎨 Improve writing av json

Signed-off-by: Daniel <845765@qq.com>

Author: 88250

kernel/av/av.go

@@ -659,9 +659,11 @@ func SaveAttributeView(av *AttributeView) (err error) {
 	}
 
 	avJSONPath := GetAttributeViewDataPath(av.ID)
-	if err = filelock.WriteFile(avJSONPath, data); err != nil {
-		logging.LogErrorf("save attribute view [%s] failed: %s", av.ID, err)
-		return
+	if err = util.WriteFileByMmap(avJSONPath, data); nil != err {
+		if err = filelock.WriteFile(avJSONPath, data); nil != err {
+			logging.LogErrorf("save attribute view [%s] failed: %s", av.ID, err)
+			return
+		}
 	}
 
 	cache.SetAVData(av.ID, data)

kernel/filesys/tree.go

@@ -32,7 +32,6 @@ import (
 	"github.com/88250/lute/html"
 	"github.com/88250/lute/parse"
 	"github.com/88250/lute/render"
-	mmap "github.com/edsrzf/mmap-go"
 	jsoniter "github.com/json-iterator/go"
 	"github.com/panjf2000/ants/v2"
 	"github.com/siyuan-note/dataparser"
@@ -254,7 +253,7 @@ func WriteTree(tree *parse.Tree) (size uint64, err error) {
 		}
 	}
 
-	if err = writeTreeByMmap(filePath, data); nil != err {
+	if err = util.WriteFileByMmap(filePath, data); nil != err {
 		if err = writeTreeByWriteFile(filePath, data); nil != err {
 			return
 		}
@@ -281,39 +280,6 @@ func writeTreeByWriteFile(filePath string, data []byte) (err error) {
 	return
 }
 
-func writeTreeByMmap(filePath string, data []byte) (err error) {
-	f, err := filelock.OpenFile(filePath, os.O_RDWR|os.O_CREATE, 0644)
-	if err != nil {
-		return
-	}
-	defer filelock.CloseFile(f)
-
-	if err = f.Truncate(int64(len(data))); err != nil {
-		msg := fmt.Sprintf("truncate file [%s] failed: %s", filePath, err)
-		logging.LogErrorf(msg)
-		err = errors.New(msg)
-		return
-	}
-
-	m, err := mmap.Map(f, mmap.RDWR, 0)
-	if err != nil {
-		msg := fmt.Sprintf("map file [%s] failed: %s", filePath, err)
-		logging.LogErrorf(msg)
-		err = errors.New(msg)
-		return
-	}
-	defer m.Unmap()
-
-	copy(m, data)
-	if err = m.Flush(); err != nil {
-		msg := fmt.Sprintf("flush data [%s] failed: %s", filePath, err)
-		logging.LogErrorf(msg)
-		err = errors.New(msg)
-		return
-	}
-	return
-}
-
 func prepareWriteTree(tree *parse.Tree) (data []byte, filePath string, err error) {
 	luteEngine := util.NewLute() // 不关注用户的自定义解析渲染选项
 

kernel/util/mmap.go

@@ -0,0 +1,68 @@
+// SiYuan - Refactor your thinking
+// Copyright (c) 2020-present, b3log.org
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package util
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	mmap "github.com/edsrzf/mmap-go"
+	"github.com/siyuan-note/filelock"
+	"github.com/siyuan-note/logging"
+)
+
+// WriteFileByMmap 使用内存映射将 data 原地覆写到 filePath。
+//
+// 流程：OpenFile(O_RDWR|O_CREATE) → Truncate 到精确长度 → mmap.Map(RDWR) →
+// copy 写入 → Flush → Unmap，全程持有 filelock 的进程内互斥锁，避免并发写冲突。
+//
+// 相比 filelock.WriteFile（临时文件 + rename + fsync），此路径在进程级 I/O
+// 计数（IO Write Bytes）上几乎不计——copy 是纯内存写，不经过 I/O 子系统，
+// 只有 Flush 会产生极少量计入。出错时由调用方回退到 filelock.WriteFile。
+func WriteFileByMmap(filePath string, data []byte) (err error) {
+	f, err := filelock.OpenFile(filePath, os.O_RDWR|os.O_CREATE, 0644)
+	if err != nil {
+		return
+	}
+	defer filelock.CloseFile(f)
+
+	if err = f.Truncate(int64(len(data))); err != nil {
+		msg := fmt.Sprintf("truncate file [%s] failed: %s", filePath, err)
+		logging.LogErrorf(msg)
+		err = errors.New(msg)
+		return
+	}
+
+	m, err := mmap.Map(f, mmap.RDWR, 0)
+	if err != nil {
+		msg := fmt.Sprintf("map file [%s] failed: %s", filePath, err)
+		logging.LogErrorf(msg)
+		err = errors.New(msg)
+		return
+	}
+	defer m.Unmap()
+
+	copy(m, data)
+	if err = m.Flush(); err != nil {
+		msg := fmt.Sprintf("flush data [%s] failed: %s", filePath, err)
+		logging.LogErrorf(msg)
+		err = errors.New(msg)
+		return
+	}
+	return
+}