diff --git a/.gitignore b/.gitignore
index 5ae335c1..dff3bdf4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -21,6 +21,7 @@ bin/
 
 *.data
 *.db
+*.log
 
 .DS_Store
 
diff --git a/pkg/download/downloader.go b/pkg/download/downloader.go
index 0dc49994..0067e197 100644
--- a/pkg/download/downloader.go
+++ b/pkg/download/downloader.go
@@ -72,7 +72,7 @@ func NewDownloader(cfg *DownloaderConfig) *Downloader {
 		}
 	}
 
-	logPanic(cfg.StorageDir)
+	logPanic(filepath.Join(cfg.StorageDir, "logs"))
 	return d
 }
 
@@ -640,22 +640,12 @@ func (d *Downloader) doContinue(task *Task) (err error) {
 
 // redirect stderr to log file, when panic happened log it
 func logPanic(logDir string) {
-	fp := filepath.Join(logDir, "crash.log")
-	// if log file not exists, create it
-	var f *os.File
-	if _, err := os.Stat(fp); err != nil {
-		if !os.IsNotExist(err) {
-			return
-		}
-		f, err = os.Create(fp)
-		if err != nil {
-			return
-		}
-	} else {
-		f, err = os.OpenFile(fp, os.O_APPEND|os.O_WRONLY, 0644)
-		if err != nil {
-			return
-		}
+	if err := util.CreateDirIfNotExist(logDir); err != nil {
+		return
+	}
+	f, err := os.Create(filepath.Join(logDir, "crash.log"))
+	if err != nil {
+		return
 	}
 	paniclog.RedirectStderr(f)
 }
diff --git a/pkg/util/path.go b/pkg/util/path.go
index 9f9fc1ed..f594297b 100644
--- a/pkg/util/path.go
+++ b/pkg/util/path.go
@@ -3,7 +3,6 @@ package util
 import (
 	"errors"
 	"fmt"
-	"io"
 	"os"
 	syspath "path"
 	"strings"
@@ -83,17 +82,9 @@ func GetSingleDir(paths []string) string {
 	return dir
 }
 
-// check directory is empty
-func isEmpty(name string) (bool, error) {
-	f, err := os.Open(name)
-	if err != nil {
-		return false, err
+func CreateDirIfNotExist(dir string) error {
+	if _, err := os.Stat(dir); os.IsNotExist(err) {
+		return os.MkdirAll(dir, 0o777)
 	}
-	defer f.Close()
-
-	_, err = f.Readdirnames(1) // Or f.Readdir(1)
-	if err == io.EOF {
-		return true, nil
-	}
-	return false, err // Either not empty or error, suits both cases
+	return nil
 }
diff --git a/ui/flutter/lib/app/modules/setting/views/setting_view.dart b/ui/flutter/lib/app/modules/setting/views/setting_view.dart
index 1e4e66b6..91c8c3bb 100644
--- a/ui/flutter/lib/app/modules/setting/views/setting_view.dart
+++ b/ui/flutter/lib/app/modules/setting/views/setting_view.dart
@@ -35,7 +35,7 @@ class SettingView extends GetView<SettingController> {
     debounceSave({bool needRestart = false}) {
       var completer = Completer<void>();
       timer?.cancel();
-      timer = Timer(const Duration(milliseconds: 500), () {
+      timer = Timer(const Duration(milliseconds: 1000), () {
         appController
             .saveConfig()
             .then(completer.complete)
diff --git a/ui/flutter/lib/util/log_util.dart b/ui/flutter/lib/util/log_util.dart
index d7611756..dbeb41a0 100644
--- a/ui/flutter/lib/util/log_util.dart
+++ b/ui/flutter/lib/util/log_util.dart
@@ -1,19 +1,23 @@
 import 'dart:io';
-
 import 'package:flutter/foundation.dart';
 import 'package:logger/logger.dart';
-
 import 'util.dart';
 
 final logger = Logger(
-  printer: PrettyPrinter(),
+  filter: ProductionFilter(),
+  printer: LogfmtPrinter(),
   output: buildOutput(),
 );
 
 buildOutput() {
-  // if is debug mode, output to console
+  // if is debug mode, don't log to file
   if (!kDebugMode && Util.isDesktop()) {
-    return FileOutput(file: File('log.txt'));
+    const logDirPath = 'logs';
+    var logDir = Directory(logDirPath);
+    if (!logDir.existsSync()) {
+      logDir.createSync();
+    }
+    return FileOutput(file: File('$logDirPath/client.log'));
   }
   return null;
 }
diff --git a/ui/flutter/lib/util/message.dart b/ui/flutter/lib/util/message.dart
index fd2f75e1..23be0dbb 100644
--- a/ui/flutter/lib/util/message.dart
+++ b/ui/flutter/lib/util/message.dart
@@ -12,7 +12,7 @@ void showErrorMessage(msg) {
     Get.snackbar(title, ((msg as dynamic).message as Result).msg!);
     return;
   }
-  Get.snackbar(title, msg);
+  Get.snackbar(title, msg.toString());
 }
 
 void showMessage(title, msg) {