From b4a761d0717ac696708d3f7269d0d4634cf853f9 Mon Sep 17 00:00:00 2001
From: Daniel <845765@qq.com>
Date: Sat, 7 Feb 2026 11:49:58 +0800
Subject: [PATCH] :zap: Reduce the memory usage when exporting documents
 containing numerous references
 https://github.com/siyuan-note/siyuan/issues/16982

Signed-off-by: Daniel <845765@qq.com>
---
 kernel/model/export.go | 39 +++++++++++++++++++++++++++------------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/kernel/model/export.go b/kernel/model/export.go
index 9929efacb..70dbe32fb 100644
--- a/kernel/model/export.go
+++ b/kernel/model/export.go
@@ -2241,10 +2241,10 @@ func ExportMarkdownContent(id string, refMode, embedMode int, addYfm, fillCSSVar
 	return
 }
 
-func exportMarkdownContent(id, ext string, exportRefMode int, defBlockIDs []string, singleFile bool, treeCache map[string]*parse.Tree) (tree *parse.Tree, exportedMd string, isEmpty bool) {
-	tree, err := loadTreeWithCache(id, treeCache)
+func exportMarkdownContent(rootID, ext string, exportRefMode int, defBlockIDs []string, singleFile bool, treeCache map[string]*parse.Tree) (tree *parse.Tree, exportedMd string, isEmpty bool) {
+	tree, err := loadTreeWithCache(rootID, treeCache)
 	if err != nil {
-		logging.LogErrorf("load tree by block id [%s] failed: %s", id, err)
+		logging.LogErrorf("load tree by block id [%s] failed: %s", rootID, err)
 		return
 	}
 
@@ -2263,7 +2263,7 @@ func exportMarkdownContent(id, ext string, exportRefMode int, defBlockIDs []stri
 		}
 	}
 
-	exportedMd = exportMarkdownContent0(id, tree, "", false, false, false,
+	exportedMd = exportMarkdownContent0(rootID, tree, "", false, false, false,
 		ext, exportRefMode, Conf.Export.BlockEmbedMode, Conf.Export.FileAnnotationRefMode,
 		Conf.Export.TagOpenMarker, Conf.Export.TagCloseMarker,
 		Conf.Export.BlockRefTextLeft, Conf.Export.BlockRefTextRight,
@@ -3066,8 +3066,21 @@ func resolveFootnotesDefs(refFootnotes *[]*refAsFootnotes, currentTree *parse.Tr
 
 	footnotesDefBlock = &ast.Node{Type: ast.NodeFootnotesDefBlock}
 	var rendered []string
+
+	var defIDs []string
 	for _, foot := range *refFootnotes {
-		t, err := loadTreeWithCache(foot.defID, treeCache)
+		defIDs = append(defIDs, foot.defID)
+	}
+	defIDs = gulu.Str.RemoveDuplicatedElem(defIDs)
+	bts := treenode.GetBlockTrees(defIDs)
+	for _, foot := range *refFootnotes {
+		bt := bts[foot.defID]
+		if nil == bt {
+			logging.LogWarnf("not found block tree for footnote def [%s] refNum [%s]", foot.defID, foot.refNum)
+			continue
+		}
+
+		t, err := loadTreeWithCache(bt.RootID, treeCache)
 		if nil != err {
 			logging.LogWarnf("load tree for footnote def [%s] refNum [%s] failed: %s", foot.defID, foot.refNum, err)
 			continue
@@ -3417,8 +3430,8 @@ func exportPandocConvertZip(baseFolderName string, docPaths, defBlockIDs []strin
 	assetsOldNew, assetsNewOld := map[string]string{}, map[string]string{}
 	luteEngine := util.NewLute()
 	for i, p := range docPaths {
-		id := util.GetTreeID(p)
-		tree, md, isEmpty := exportMarkdownContent(id, ext, exportRefMode, defBlockIDs, false, treeCache)
+		rootID := util.GetTreeID(p)
+		tree, md, isEmpty := exportMarkdownContent(rootID, ext, exportRefMode, defBlockIDs, false, treeCache)
 		if nil == tree {
 			continue
 		}
@@ -3437,7 +3450,7 @@ func exportPandocConvertZip(baseFolderName string, docPaths, defBlockIDs []strin
 		hash := fmt.Sprintf("%x", sha1.Sum([]byte(md)))
 		if gulu.File.IsExist(writePath) && hash != wrotePathHash[writePath] {
 			// 重名文档加 ID
-			p = hPath + "-" + id + ext
+			p = hPath + "-" + rootID + ext
 			writePath = filepath.Join(exportFolder, p)
 		}
 		writeFolder := filepath.Dir(writePath)
@@ -3743,13 +3756,15 @@ func exportRefTrees(tree *parse.Tree, defBlockIDs *[]string, retTrees, treeCache
 	*defBlockIDs = gulu.Str.RemoveDuplicatedElem(*defBlockIDs)
 }
 
-func loadTreeWithCache(id string, treeCache map[string]*parse.Tree) (tree *parse.Tree, err error) {
-	if tree = treeCache[id]; nil != tree {
+// loadTreeWithCache 加载树时优先从缓存获取，避免重复加载同一棵树
+// 注意传入的 rootID 必须是树的根节点 ID，不能是树中任意节点的 ID，否则会导致缓存失效和重复加载树
+func loadTreeWithCache(rootID string, treeCache map[string]*parse.Tree) (tree *parse.Tree, err error) {
+	if tree = treeCache[rootID]; nil != tree {
 		return
 	}
-	tree, err = LoadTreeByBlockID(id)
+	tree, err = LoadTreeByBlockID(rootID)
 	if nil == err && nil != tree {
-		treeCache[id] = tree
+		treeCache[rootID] = tree
 	}
 	return
 }