Tag: performance

List<T> is a growable heap collection; Span<T> and ReadOnlySpan<T> are stack-only views over memory you already own. Use List<T> for anything you store, return from async, or grow; Span<T> for a mutable allocation-free view in a synchronous method; ReadOnlySpan<T> for read-only parsing over strings, u8 literals, and slices.

Use Parallel.ForEach for CPU-bound work over in-memory data, Parallel.ForEachAsync for async I/O over many items with a concurrency cap, and Task.WhenAll for a small fixed fan-out where you want every operation in flight and need the results back.

Use string interpolation for one-shot composition of a fixed set of values; use StringBuilder when you append in a loop or across an unknown number of pieces. The dividing line is the loop, not the number of values.

.NET 11 Preview 4 ships DeflateEncoder, GZipEncoder, and ZLibEncoder plus matching decoders so you can compress straight into a Span<byte> with OperationStatus, no Stream required.

For read-heavy paths in .NET 11, plain EF Core with AsNoTracking is within ~5% of Dapper. Reach for compiled queries on a profiled single-row hot path, and Dapper only for the lowest latency or SQL LINQ can't express.

Plain JIT with Dynamic PGO wins steady-state throughput, ReadyToRun cuts startup with zero code changes, and Native AOT gives the smallest, fastest-starting binary at the cost of reflection and dynamic code. Pick by deployment shape, not raw benchmarks.

Microsoft moved Copilot Studio's WASM engine from .NET 8 to .NET 10. The dual JIT/AOT package, fingerprinting, and WasmStripILAfterAOT explain the numbers.

Step-by-step guide to finding and fixing jank in Flutter 3.27 with DevTools: profile mode, the Performance overlay, the Frame Analysis tab, the CPU Profiler, raster vs UI thread, shader warm-up, and Impeller-specific gotchas. Tested on Flutter 3.27.1, Dart 3.11, DevTools 2.40.

When async/await is not enough: spawn a Dart isolate to run CPU-bound work off the UI thread. Isolate.run, Flutter's compute, long-lived workers with SendPort/ReceivePort, what can cross the boundary, and the JS/web caveat. Tested on Dart 3.11 and Flutter 3.27.1.

Three ways to wrap a T[] in a ReadOnlyMemory<T> in .NET 11: the implicit conversion, the explicit constructor, and AsMemory(). When each is the right call.