How to improve applications performance which is hosted in cloud ?

Improving the performance of an application hosted in Microsoft Azure involves a combination of optimizing your application code, leveraging Azure services, and following best practices for cloud-based deployments. Here are some specific steps you can take to enhance the performance of your Azure-hosted application:

Choose the Right Azure Services: Select Azure services that align with your application's needs. For example, Azure App Service, Azure Functions, Azure Kubernetes Service (AKS), and Azure Virtual Machines offer different levels of control and scalability. Choose the appropriate service based on your workload.

Scale Horizontally: Leverage Azure's scaling capabilities to handle increased traffic. Implement auto-scaling for your application to dynamically adjust resources based on demand.

Content Delivery Network (CDN): Use Azure CDN to distribute content globally, reducing latency for users by caching static assets closer to them.

Azure Front Door or Azure Traffic Manager: Utilize services like Azure Front Door or Azure Traffic Manager for load balancing and to route traffic to the nearest and healthiest endpoint, improving availability and response times.

Azure SQL Database Optimization: If you're using Azure SQL Database, optimize query performance by creating appropriate indexes, partitioning tables, and leveraging features like query performance insights.

Azure Redis Cache: Implement Azure Redis Cache to store frequently accessed data in-memory, reducing the need to query the database for every request.

Azure Application Insights: Integrate Application Insights for real-time monitoring, performance tracking, and identifying bottlenecks in your application.

Use Managed Services: Azure offers a range of managed services like Azure Cosmos DB, Azure Search, and Azure Functions that are optimized for performance and scalability.

Geo-Replication: If your application is used across different regions, use Azure's geo-replication features to replicate data and ensure low-latency access for users.

Azure Blob Storage: Store static assets, media files, and other large objects in Azure Blob Storage to offload the web server and improve load times.

Optimize Network Traffic: Use Azure ExpressRoute for dedicated private network connections between Azure and your on-premises infrastructure to minimize latency and improve data transfer rates.

Use Azure Availability Zones: Deploy resources across Azure Availability Zones for high availability and redundancy, reducing the risk of downtime due to infrastructure failures.

Azure Managed Kubernetes (AKS): If using AKS, optimize your containerized applications by configuring appropriate resource limits, managing pod scaling, and monitoring performance.

Compress Data: Enable data compression for web resources to reduce transfer times and improve page load speed.

Azure Functions Cold Starts: If using Azure Functions, implement strategies to minimize cold starts by using warm-up requests or utilizing Premium Plan features.

Azure Virtual Network: Use Azure Virtual Network to isolate your application from other resources and optimize network traffic.

Regular Performance Testing: Conduct regular performance testing and load testing to identify performance bottlenecks and validate your optimizations.

Azure Cost Management: Optimize resource utilization to avoid overprovisioning and control costs while maintaining performance.

Remember that performance optimization is an ongoing process. Continuously monitor your application's performance using Azure monitoring tools and make adjustments as needed. Each application is unique, so tailor these recommendations to your specific requirements and architecture.

How to improve web applications performance?

Improving application performance is a critical aspect of software development, ensuring that your application runs smoothly, responds quickly, and provides a positive user experience. Here are several strategies and best practices you can consider to enhance your application's performance:

Identify Bottlenecks: Begin by profiling your application to identify performance bottlenecks. Use profiling tools to pinpoint areas of your code that consume the most time and resources.

Optimize Algorithms and Data Structures: Choose efficient algorithms and data structures for your application's operations. Using the right algorithms can significantly improve execution speed.

Caching: Implement caching mechanisms to store frequently used data in memory. This reduces the need to fetch data from slower data sources, such as databases.

Database Optimization: Optimize database queries by ensuring they are properly indexed, avoiding unnecessary joins, and using query optimization techniques provided by your database management system.

Minimize Network Latency:Reduce the number of network requests and minimize data transferred between the client and server. Use techniques like data compression and HTTP/2 to optimize network performance.

Code Profiling and Analysis: Regularly profile your code to identify performance bottlenecks, memory leaks, and other issues. Tools like profilers and performance analysis tools can help you diagnose problems.

Parallelism and Concurrency: Utilize parallel processing and concurrency to take advantage of multi-core processors. This can improve execution speed for tasks that can be performed simultaneously.

Asynchronous Programming: Employ asynchronous programming techniques, especially for I/O-bound tasks. This prevents blocking and allows your application to continue processing other tasks while waiting for I/O operations to complete.

Resource Management: Properly manage resources like memory, file handles, and database connections. Release resources when they are no longer needed to prevent resource leaks.

Optimize UI Rendering: For graphical applications, optimize UI rendering by reducing unnecessary redraws and leveraging techniques like virtualization and lazy loading.

Reduce External Dependencies: Minimize external dependencies that might introduce performance overhead. Be cautious with third-party libraries and services that could slow down your application.

Load Testing: Conduct load testing to simulate heavy user traffic and identify how your application performs under stress. This can help you uncover performance issues that might only occur in high-demand scenarios.

Content Delivery Networks (CDNs): Use CDNs to serve static assets like images, CSS, and JavaScript files. CDNs distribute content across multiple servers to improve load times for users.

Continuous Monitoring: Implement monitoring tools to continuously monitor the performance of your application in real-time. This allows you to identify and address performance issues promptly.

Regular Code Reviews: Encourage regular code reviews to ensure that performance considerations are part of the development process. Peer review can help catch potential performance issues early.

Optimize Front-End Performance: Minimize the use of large images, optimize CSS and JavaScript files, and reduce the number of HTTP requests to improve page load times.

Remember that performance optimization is an ongoing process. Regularly monitor your application's performance, gather user feedback, and be prepared to make optimizations as your application evolves. Prioritize the most impactful changes based on the specific performance challenges your application faces

What is your role in the ongoing project as an Engineering Manager?

In the ongoing project, my role as the Engineering Manager involves overseeing and coordinating various aspects of the project's technical development. I work closely with the project team, including developers, designers, and other stakeholders, to ensure that the project progresses smoothly and efficiently.

My responsibilities include:

Team Management: I lead and manage the engineering team of 42 engineers including tech lead, tech architect and solution architect, ensuring that each member understands their responsibilities and is working cohesively toward project goals. I provide guidance, support, and mentorship to help the team succeed.

Project Planning: I collaborate with other departments to define project goals, scope, and milestones. I work to create a clear project plan that outlines tasks, deadlines, and resource allocation.

Technical Guidance: I provide technical expertise and guidance to the team when they encounter challenges or need assistance. I help make decisions about architecture, technology choices, and implementation strategies.

Communication: I facilitate effective communication within the team and with stakeholders. Regular status updates, meetings, and reports keep everyone informed about the project's progress and any potential issues.

Problem Solving: I'm involved in troubleshooting and resolving technical issues that may arise during the project. I encourage creative problem-solving and collaborate with the team to find solutions.

Risk Management: I identify potential risks to the project's success and develop mitigation strategies. This involves anticipating challenges and taking proactive steps to address them.

Quality Assurance: I ensure that the team follows best practices for code quality, testing, and documentation. This contributes to the overall reliability and maintainability of the project.

Performance Evaluation: I conduct performance reviews and provide feedback to team members, helping them identify their strengths and areas for improvement.

Adaptation: Projects can change direction due to various factors. I help the team adapt to changes, whether they're related to requirements, timelines, or priorities.

Stakeholder Management: I liaise with project stakeholders, including upper management and non-technical teams, to keep them informed about progress and to address any concerns.

What is latency and throughput in performance testing?

 Latency and throughput are two important metrics used to assess the performance of software applications or systems. They provide insights into how well an application functions under different loads and conditions.

Latency: It refers to the time it takes for a request to travel from the source to the destination and receive a response. In the context of software or application performance testing, latency measures the delay or time lag between sending a request and receiving a response. It is typically measured in milliseconds (ms) or microseconds (µs). Low latency is desirable because it indicates that the application can quickly respond to user requests.

There are different types of latency, including:

Network Latency: The time taken for data to travel across a network from the sender to the receiver.

Server Latency: The time taken for a server to process a request and generate a response.

Database Latency: The time taken for a database to process a query and return the results.

Throughput: It is also known as "bandwidth" or "capacity," measures the rate at which a system can process and handle a certain number of requests or transactions over a given period of time. It is usually measured in requests per second (RPS) or transactions per second (TPS). High throughput indicates that the system can handle a large number of requests efficiently.

Throughput can be affected by factors such as network bandwidth, server processing power, and the efficiency of the software architecture.

In software or application performance testing:

Latency Testing: This involves measuring the time it takes for individual requests to complete and analyzing the distribution of response times. It helps identify bottlenecks and areas where improvements are needed to reduce delays.

Throughput Testing: This involves stressing the system with a predefined load and measuring how many requests or transactions the system can handle per unit of time. It helps determine the system's capacity and its ability to scale under various loads.

Both latency and throughput are crucial metrics for assessing the user experience and overall health of an application. In some cases, a trade-off might be necessary between low latency and high throughput, as optimizing for one metric could affect the other. Performance testing helps ensure that an application meets the performance expectations of its users and provides insights into areas that may need optimization.

What is Project Traceability?

 Project traceability is the ability to trace and link requirements, design, development, testing, and deployment artifacts across the software development lifecycle. Traceability ensures that each requirement is met by a corresponding design element, implementation code, test case, and deployment artifact.

The primary goal of project traceability is to establish a clear relationship between various stages of the software development lifecycle and to enable stakeholders to trace back any change or issue in the software product to its origin. Traceability ensures that all requirements are met, and any changes in the requirements are appropriately tracked and managed.

Project traceability is often achieved through a traceability matrix, which is a table that links each requirement to its corresponding design element, implementation code, test case, and deployment artifact. The traceability matrix allows stakeholders to trace the progress of a requirement through each stage of the software development lifecycle and to ensure that all requirements are met.

Traceability is crucial in highly regulated industries, such as healthcare and aerospace, where software products must meet strict regulatory requirements. However, project traceability is also important in any software development project to ensure that the product meets the customer's needs and requirements and to enable effective tracking and management of changes throughout the development process.

High level vs low level design ?

High-level design and low-level design are two stages in the software design process that are used to define the architecture and functionality of a software system.

High-level design refers to the early stages of the design process where the overall architecture and requirements of the software system are defined. This includes defining the system's modules, interfaces, and data structures, as well as its overall functionality and user interface. High-level design provides an abstract view of the system and focuses on the system's major components and their interactions.

On the other hand, low-level design involves the detailed design of individual modules or components within the software system. This includes defining the algorithms, data structures, and programming language constructs to be used in each component. Low-level design focuses on the specific implementation details of the system and provides a more detailed view of how the system will function.

In summary, high-level design focuses on the overall architecture and functionality of the system, while low-level design focuses on the specific details of individual components within the system. Both are important stages in the software design process and contribute to the development of a high-quality, efficient software system.

What happens when you type a URL into your browser?

URL stands for Uniform Resource Locator. URL is the address of the website which you can find in the address bar of your web browser.

Example : https://www.debuggersspace.com/ 

DNS : DNS is short for Domain Name System. Like a phonebook, DNS maintains and maps the name of the website, i.e. URL, and particular IP address it links to. Every URL on the internet has a unique IP address which is of the computer which hosts the server of the website requested.

CNAME record : A Canonical Name record is a type of resource record in the Domain Name System that maps one domain name to another. This can prove convenient when running multiple services from a single IP address.

Steps for what happens when we enter a URL :

1. Browser checks cache for DNS entry to find the corresponding IP address of website.
   It looks for following cache. If not found in one, then continues checking to the next until found.
   • Browser Cache
   • Operating Systems Cache
   • Router Cache
   • ISP Cache
2. If not found in cache, ISP’s (Internet Service Provider) DNS server initiates a DNS query to find IP address of server that hosts the domain name.
   The requests are sent using small data packets that contain information content of request and IP address it is destined for.
3. Browser initiates a TCP (Transfer Control Protocol) connection with the server 
4. Browser sends an HTTP request to the web server. GET or POST request.
5. Server on the host computer handles that request and sends back a response. It assembles a response in some format like JSON, XML and HTML.
6. Server sends out an HTTP response along with the status of response.
7. Browser displays HTML content
8. Finally, Done.

What is cloud computing?

Cloud computing is the delivery of computing services—including servers, storage, databases, networking, software, analytics, and intelligence—over the Internet (“the cloud”) to offer faster innovation, flexible resources, and economies of scale.

here are several examples of cloud computing applications -

1. Cloud service would be streaming platforms for audio or video, where the actual media files are stored remotely.

2. Data storage platforms like Google Drive, Dropbox, OneDrive

.Net core interview Q & A

Top 20 Q & A

 https://www.dotnettricks.com/learn/aspnetcore/top-20-asp-net-core-interview-questions-and-answers

Top 60

https://www.qfles.com/interview-question/asp-net-core-interview-questions

Can an abstract class have a constructor ?

Yes, an abstract class can have a constructor. 

In general, a class constructor is used to initialize fields. Along the same lines, an abstract class constructor is used to initialize fields of the abstract class.

An abstract class constructor can also be used to execute code that is relevant for every child class. This prevents duplicate code.

You can not create an instance of an abstract class, so what is the use of a constructor in an abstract class?

You can not create an instance of the abstract class, we can create instances of the classes that are derived from the abstract class.

So, when an instance of the derived class is created, the parent abstract class constructor is automatically called.

Note: Abstract class cant be directly instantiated, The abstract class constructors get executed thru a derived class. So, it is a good practice to use a protected modifier with an abstract class constructor,using public doesn't make sense.

.NET Framework vs .Net Core 3.1

 

Sr. No.	Comparison	.Net Framework	.Net Core 3.1
1	Cross Platforms	.Net framework runs only on windows	.Net core is cross-platform, it operates on Windows, Linux, and Mac operating systems
2	Performance	Slow	Better
3	Application supported	the .NET framework is for developing desktop applications, web applications, and web services, WPF, ASP.NET MVC	MVC core 3.x
4	WCF/ WPF/WWF	Yes	No
5	Desktop Based	WPF, Winforms.	Nothing for desktop
6	Packaging	Packaged as big framework	Delivered via modularity using Nuget
7	Microservice Support	No	Yes
8	CLI Tools	More IDE Based	Full CLI command supported
9	Mobile Compatibility	No direct support	with .Net standard compatible with Xamarin
9	Cloud	Runs only on windows	Yes