Desktop Application Desktop Application Performance 2

Question 1

What is a 'memory profile' in the context of desktop application performance?

Accepted Answer

A snapshot of memory allocations that identifies leaks and high-usage areas

Answer

A memory profile captures heap allocation data over time, allowing developers to detect memory leaks, excessive allocations, and objects that are not being garbage collected.

Question 2

What is the benefit of using a thread pool in a desktop application?

Accepted Answer

Reusing a fixed set of threads for multiple tasks to avoid the overhead of creating and destroying threads

Answer

Thread pools maintain pre-created threads, dispatching tasks to available workers and avoiding the expensive overhead of thread creation and teardown for each task.

Question 3

What causes 'GDI object leak' in a Windows desktop application?

Accepted Answer

Not releasing GDI objects like pens, brushes, and bitmaps after use

Answer

Windows has a per-process limit on GDI objects; if pens, brushes, fonts, or bitmaps created with GDI functions are not deleted after use, the application exhausts this limit and rendering fails.

Question 4

What is 'dirty region' rendering in desktop GUI frameworks?

Accepted Answer

Only redrawing parts of the screen that have changed rather than the entire window

Answer

Dirty region (or invalidation) rendering tracks which screen areas need repainting and only redraws those regions, reducing CPU and GPU work per frame.

Question 5

How does connection pooling improve the performance of a desktop application accessing a database?

Accepted Answer

Reuses existing database connections instead of creating a new one for every query

Answer

Opening a database connection is expensive; pooling maintains a set of open connections that are reused across queries, significantly reducing connection overhead.

Desktop Application Practice Test

Desktop Application Practice Test

Desktop Application Desktop Application Performance 2