Packing never end

when i pacing for android ,it never end.my pc: cpu e5200 , ram 4gmb UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Max memory allowance for cook 16384mb min free memory 0mb UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Mobile HDR setting 1 UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Creating asset registry UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooked content cleared for platform Android_PVRTC UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Unable to read previous cook inisettings for platform Android_PVRTC invalidating cook UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Sandbox cleanup took 0.204 seconds for platforms Android_PVRTC iterative false UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/Tutorial/Landscape/LandscapeWalkThrough -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/Tutorial/Landscape/LandscapeWalkThrough.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: No exports found (or all exports are editor-only) for LandscapeWalkThrough. Package will not be saved. UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/EngineFonts/Roboto -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Roboto.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: Finished SavePackage E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Roboto.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/EngineFonts/Faces/RobotoBold -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoBold.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: Finished SavePackage E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoBold.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/EngineFonts/Faces/RobotoBoldItalic -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoBoldItalic.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: Finished SavePackage E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoBoldItalic.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/EngineFonts/Faces/RobotoItalic -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoItalic.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: Finished SavePackage E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoItalic.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/EngineFonts/Faces/RobotoLight -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoLight.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: Finished SavePackage E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoLight.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogCook: Display: Cooking /Engine/EngineFonts/Faces/RobotoRegular -> E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoRegular.uasset UATHelper: 打包 (Android (PVRTC)): Cook: LogSavePackage: Display: Finished SavePackage E:/ue_project/aaa/Saved/Cooked/Android_PVRTC/Engine/Content/EngineFonts/Faces/RobotoRegular.uasset