Software Architecture (SA) provides a formal basis to describe and analyze a software system as a collection of components and their interactions (connectors). However, the current understanding and specification for non-functional properties inside a software architecture are still insufficient. Most of today?s architecture specification and analysis only support functional properties. They overlook the non-functional properties like performance, security, reliability, etc. This paper attempts to tackle the problem by providing an Architecture Description Language (ADL), xSADL4PE. xSADL4PE integrates both functional property and non-functional property (performance evaluation) into the architecture specification. It can help designers to give both quality and quantity specification at the design stage.