How to know if a process window is live or hung?

Problem: In real time systems, normally application will be running for all the time, 365 days and 24/7. Some dashboards will be displaying the mission critical parameters like trends, alarms events etc. How do we make sure that the dashboard windows of the application are showing correct real time data and it is not hung?

Analysis: The application or the window may hang due to various reasons like OS going to hibernate mode or due to some exception the window thread may not be showing the live real time data. To make sure that the windows are not freeze, we need some mechanism for alerting the user in such cases.

Solution: The solution is to have a watchdog process, that keeps on monitoring all the threads of the running application. A mechanism to send alive time out message and receive the acknowledgement from the threads of the main application. In case the application hangs there should be a way to let the user know that the main application has hang and needs to be restarted. It can be further expanded to collect dumps (for example in case of any application hang or crash Windows operating system asks for sending the dumps to Microsoft) for analyzing the hang or crash issue. Watchdog process can also be utilized for collecting and sending dumps of the main application in case of hang or crash.

Comments

Real time data to web application using Microsoft Signal R and Razor Pages

Today we are going to learn how to create razor pages and how to send run time value to the razor page using Signal R Create a new .NET core web application Add Signal R library by, Add Client-Side Library dialog in the project, for Provider select "unpkg" and select the latest version from the drop down For Library, enter @aspnet/signalr@1, Add a new folder to the project named as Hubs The chat hub class inherits from HUb class that manages connections and messaging The send message is called to send the message to all the clients. MyHub.cs file contains the following code using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.SignalR; //using System.Threading.Tasks; namespace SignalRSample.Hubs { public class MyHub : Hub { public async Task SendMessage(string user, string message) { ...

CRUD operation with WCF service and WPF client

The database restored on local server WCF Service is talking to the database. Used Visual Studio 2019, entity framework 6 for data base operations from the service. The service exposes the following API’s. The WCF contracts has both synchronous and asynchronous API's The client is in WPF. It has three windows, main window, customer window and order window as follows. The client uses the WCF service for database operations. When customer button is clicked, the customer window is displayed as below. We can perform CRUD operation from it. The customer can be searched based on ID. New customer window The order button launched order window. It has combo box to choose the customer ID. On selecting the ID, the order details are displayed in the data grid as follows. The source code is available in the GIT hub, URL below: https://github.com/SwagatikaGoswami/WPF_WCF_CRUD.git

Online Exam App with .NET Core Web API and Blazor Client

We will develop an app that can host online exam. It will have the feature to register user, allow the user to log in. Dashboard for creating sample tests. The code is shared in GIT hub repository https://github.com/ SwagatikaGoswami/ OnlineExamApp.git The database is MySQL database. The server is a WEB API .NET Core service that uses entity framework for DB operations. The client is a web assembly blazor application. The password stored in the database is encrypted. Register window is as follows. It checks for the mandatory fields. The log in page is as follows: The admin dashboard after logging in The admin dashboard when new test button is clicked. It uses a Blazor component for adding new test samples.

What I learned today

Search This Blog