MCSD MCSD Performance Optimization and Scalability 2

Question 1

In Azure App Service, which feature allows you to automatically increase or decrease the number of running instances based on CPU or memory metrics?

Accepted Answer

Autoscale

Answer

Deployment slots

Answer

Hybrid connections

Answer

Traffic Manager

Question 2

What is the purpose of the ArrayPool<T> class in .NET when dealing with high-throughput scenarios?

Accepted Answer

To rent and return pre-allocated arrays, reducing garbage collection pressure

Answer

To synchronize array access across multiple threads safely

Answer

To store arrays in Azure Blob Storage for large datasets

Answer

To serialize arrays to JSON without extra allocations

Question 3

Which BenchmarkDotNet attribute is required to mark a method for micro-benchmarking in .NET?

Accepted Answer

[Benchmark]

Answer

[Measure]

Answer

[Perf]

Answer

[TimedTest]

Question 4

What does horizontal scaling (scale out) mean for an Azure-hosted web application compared to vertical scaling (scale up)?

Accepted Answer

Adding more VM instances to distribute load, rather than upgrading a single VM to a larger size

Answer

Partitioning the database into more shards rather than increasing database DTUs

Answer

Increasing thread count within the same process rather than adding worker processes

Answer

Expanding geographic regions rather than adding capacity in one region

Question 5

In Entity Framework Core, what does the Select() projection do to improve query performance compared to loading full entities?

Accepted Answer

It retrieves only the specified columns from the database instead of all columns

Answer

It caches query results in memory to avoid repeated database hits

Answer

It executes the query asynchronously on a background thread

Answer

It splits the query into multiple batches to reduce lock contention

Question 6

Which Azure service should you use to distribute global traffic to the nearest application endpoint to reduce latency for US users?

Accepted Answer

Azure Front Door or Azure Traffic Manager

Answer

Azure Load Balancer

Answer

Azure API Management

Answer

Azure Application Gateway