From 9fd1bf7b960dc19f68bd4d1dbe2945e33967bce2 Mon Sep 17 00:00:00 2001
From: Daniel <845765@qq.com>
Date: Fri, 6 Feb 2026 22:17:53 +0800
Subject: [PATCH] :zap: Writing document data by mmap to reduce disk write
 operations https://github.com/siyuan-note/siyuan/issues/16956

Signed-off-by: Daniel <845765@qq.com>
---
 kernel/filesys/tree.go | 55 +++++++++++++++++++++++++++++++++++++-----
 kernel/go.mod          |  1 +
 kernel/go.sum          |  2 ++
 3 files changed, 52 insertions(+), 6 deletions(-)

diff --git a/kernel/filesys/tree.go b/kernel/filesys/tree.go
index 8d1975104..c2e74942d 100644
--- a/kernel/filesys/tree.go
+++ b/kernel/filesys/tree.go
@@ -32,6 +32,7 @@ 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"
@@ -228,12 +229,10 @@ func WriteTree(tree *parse.Tree) (size uint64, err error) {
 		return
 	}
 
-	size = uint64(len(data))
-	if err = filelock.WriteFile(filePath, data); err != nil {
-		msg := fmt.Sprintf("write data [%s] failed: %s", filePath, err)
-		logging.LogErrorf(msg)
-		err = errors.New(msg)
-		return
+	if err = writeTreeByMmap(filePath, data); nil != err {
+		if err = writeTreeByWriteFile(filePath, data); nil != err {
+			return
+		}
 	}
 
 	if util.ExceedLargeFileWarningSize(len(data)) {
@@ -243,6 +242,50 @@ func WriteTree(tree *parse.Tree) (size uint64, err error) {
 
 	cache.SetTreeData(tree.ID, data)
 	afterWriteTree(tree)
+	size = uint64(len(data))
+	return
+}
+
+func writeTreeByWriteFile(filePath string, data []byte) (err error) {
+	if err = filelock.WriteFile(filePath, data); err != nil {
+		msg := fmt.Sprintf("write data [%s] failed: %s", filePath, err)
+		logging.LogErrorf(msg)
+		err = errors.New(msg)
+		return
+	}
+	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
 }
 
diff --git a/kernel/go.mod b/kernel/go.mod
index 86f05cdf7..96936c240 100644
--- a/kernel/go.mod
+++ b/kernel/go.mod
@@ -127,6 +127,7 @@ require (
 	github.com/dsnet/compress v0.0.1 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/ebitengine/purego v0.9.1 // indirect
+	github.com/edsrzf/mmap-go v1.2.0 // indirect
 	github.com/fatih/set v0.2.1 // indirect
 	github.com/gammazero/toposort v0.1.1 // indirect
 	github.com/gigawattio/window v0.0.0-20180317192513-0f5467e35573 // indirect
diff --git a/kernel/go.sum b/kernel/go.sum
index 03d5341e6..bc0dd8660 100644
--- a/kernel/go.sum
+++ b/kernel/go.sum
@@ -133,6 +133,8 @@ github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkp
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
 github.com/ebitengine/purego v0.9.1 h1:a/k2f2HQU3Pi399RPW1MOaZyhKJL9w/xFpKAg4q1s0A=
 github.com/ebitengine/purego v0.9.1/go.mod h1:iIjxzd6CiRiOG0UyXP+V1+jWqUXVjPKLAI0mRfJZTmQ=
+github.com/edsrzf/mmap-go v1.2.0 h1:hXLYlkbaPzt1SaQk+anYwKSRNhufIDCchSPkUD6dD84=
+github.com/edsrzf/mmap-go v1.2.0/go.mod h1:19H/e8pUPLicwkyNgOykDXkJ9F0MHE+Z52B8EIth78Q=
 github.com/emersion/go-ical v0.0.0-20240127095438-fc1c9d8fb2b6/go.mod h1:BEksegNspIkjCQfmzWgsgbu6KdeJ/4LwUZs7DMBzjzw=
 github.com/emersion/go-ical v0.0.0-20250609112844-439c63cef608 h1:5XWaET4YAcppq3l1/Yh2ay5VmQjUdq6qhJuucdGbmOY=
 github.com/emersion/go-ical v0.0.0-20250609112844-439c63cef608/go.mod h1:BEksegNspIkjCQfmzWgsgbu6KdeJ/4LwUZs7DMBzjzw=