🩸 6 Invisible .NET Performance Killers

#performance #csharp #dotnet #devtips

Even the cleanest .NET code can hide silent performance drains — the kind that only show up when your app is under real load.

Here’s a quick reference for developers and architects to spot and fix them before they bite.

⚡ 1. LINQ

Problem: Deferred execution & hidden allocations.

Fix: Push heavy queries to SQL, avoid LINQ‑to‑Objects for large datasets.

⚡ 2. Async/Await

Problem: Blocking calls & context switches.

Fix: Never block async, use ValueTask, profile the thread pool.

⚡ 3. Logging

Problem: Synchronous, verbose logs.

Fix: Structured async logging (e.g., Serilog), separate dev vs prod logging levels.

⚡ 4. Dependency Injection

Problem: Many scoped services slow startup.

Fix: Minimize scoped dependencies, modularize DI registrations.

⚡ 5. JSON Serialization

Problem: Large object graphs, GC pressure.

Fix: Use streaming serialization, paginate large collections.

⚡ 6. Entity Framework

Problem: N+1 queries via lazy loading.

Fix: Use .Include(), batch load, and analyze EF logs.

🛡️ Key Takeaways

Trust abstractions, but verify their cost.
Profile, measure, and optimize early.
Guardrails: logging, queries, DI, serialization.

💡 Pro Tip:

Pair this checklist with a profiler (e.g., dotTrace, PerfView) to see the hidden costs in action.

📄 Full deep‑dive + visual cheat sheet here:

Invisible .NET Performance Killers — Framework Features That Fail at Scale

#dotnet #csharp #performance #cleanarchitecture #devtips #entityframework #asyncawait #logging #dependencyinjection #jsonserialization #linq