With the rapid development of Internet technology, more GIS technologies have been applied in WebGIS system. Then how is the performance of WebGIS system processing GIS data and functions? During the daily work of development and operations, can we find some simple methods to test the performance of WebGIS system besides the tools with high threshold (like LoadRunner)?
Due to the different roles of GIS server (like SuperMap iServer) and WebGIS client (the application system based on SuperMap iClient) in WebGIS system, there are different performance test methods. The following parts will introduce the performance analysis methods of GIS server and WebGIS client separately.
1. The analysis methods for WebGIS client (take SuperMap iClient as an example).
WebGIS client is a user access window. Its main tasks are data and map requests, data and tiles downloading and map rendering. The performance of those tasks can be tested by the developer tool of Chrome. This tool can monitor the consuming time of the client in different periods and different tasks of the whole GIS service procedure.
a. Open Chrome browser and go to the developer tool panel by F12 button. Please disable the local cache system before starting the test.
b. The network panel can record the web request details on the current page including the status, types, size, time, request and response. Through those detail information, we can analyze the performance of the current page, in order to adjust the client.
The network panel consists of the following 5 parts:
"Controls” provides the panel's function and appearance control options
"Filters” provides the network request type filtering functions
"Overview” provides the timeline information for network requests
"Requests Table” provides the network request list and detailed resource information
"Summery” provides the information of total request quantity, the amount of data transferred and loading time.
c. The Performance panel focuses on monitoring the resources consumption of the client page and analyzing the client consumption of different tasks in every period.
Through the performance panel, we can get the following information from the whole Rest map service page rendering process:
They are the status of FPS, CPU and NET resources, the page rendering snapshots, the consumption time of code processing, the video card loading status and the time consuming calculation of client page task classification.
2. The monitoring methods for GIS server (take SuperMap iServer as an example)
GIS server is the core of request processing and application analysis. Its main tasks are receiving client data and map requests, GIS function analysis and packaging and sending result data. Take the Linux platform as an example, it can quickly query and save the condition of the server hardware in the server running process through some monitor commands of system resource. Some common monitor commands are listed as follows:
a. The “top” command can dynamically check the overall performance of the system in real time. It is a practical tool that integrates the performance and operation information of various information monitoring systems.
b. The “pidstat” command is commonly used to monitor the tasks currently being managed by the Linux kernel, which is highly targeted to the core process or process group.
Besides, there are many other Linux system resource monitoring commands and each of them has its own unique advantages. We need to choose the most suitable monitoring command or command combination according to our actual server deployment and test requirements.