diff --git a/kernel/model/import.go b/kernel/model/import.go
index 941cc1ab1..3dd5dc16d 100644
--- a/kernel/model/import.go
+++ b/kernel/model/import.go
@@ -31,7 +31,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
-	"runtime/debug"
+	"runtime"
 	"sort"
 	"strconv"
 	"strings"
@@ -708,8 +708,9 @@ func ImportFromLocalPath(boxID, localPath string, toPath string) (err error) {
 		}
 		IncSync()
 	}
-	debug.FreeOSMemory()
+
 	IncSync()
+	runtime.GC()
 	return
 }
 
diff --git a/kernel/model/mount.go b/kernel/model/mount.go
index 1b7c6b74a..06b419bfb 100644
--- a/kernel/model/mount.go
+++ b/kernel/model/mount.go
@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"runtime/debug"
 	"strings"
 	"time"
 	"unicode/utf8"
@@ -132,7 +131,6 @@ func unmount0(boxID string) {
 	boxConf.Closed = true
 	box.SaveConf(boxConf)
 	box.Unindex()
-	debug.FreeOSMemory()
 }
 
 func Mount(boxID string) (alreadyMount bool, err error) {