--- title: The Fasting Developer: Memory Discipline and GC... description: A deep dive into .NET memory discipline and GC-aware coding practices. Covers how the generational garbage collector works and why short-lived objects that... canonical: https://daily.dev/posts/the-fasting-developer-memory-discipline-and-gc-awareness-in-net-5yq85h552 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: The Fasting Developer: Memory Discipline and GC Awareness in .NET | daily.dev og:description: A deep dive into .NET memory discipline and GC-aware coding practices. Covers how the generational garbage collector works and why short-lived objects that... og:url: https://daily.dev/posts/the-fasting-developer-memory-discipline-and-gc-awareness-in-net-5yq85h552 og:image: https://api.daily.dev/og/posts/5yQ85h552.png og:image:alt: The Fasting Developer: Memory Discipline and GC Awareness in .NET og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # The Fasting Developer: Memory Discipline and GC Awareness in .NET **[We Are .NET](https://daily.dev/sources/wearedotnet)** · 9 min read · 12 upvotes · 0 comments ## Summary A deep dive into .NET memory discipline and GC-aware coding practices. Covers how the generational garbage collector works and why short-lived objects that survive collections cause latency spikes. Practical techniques include: using value types and readonly structs to avoid heap allocations, Span and stackalloc for zero-allocation reads, string.Create for building strings without intermediates, SearchValues for vectorized character search in .NET 8+, ArrayPool for buffer reuse, and avoiding hidden allocations from closures and Task vs ValueTask. Includes profiling guidance using dotnet-trace and BenchmarkDotNet with [MemoryDiagnoser]. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How much memory does string.Split allocate compared to using Span for parsing a string? Splitting a string with string.Split typically allocates 72 to 96 bytes per call, since it creates a string array plus multiple substrings. Parsing the same value with ReadOnlySpan and AsSpan/LastIndexOf/TryParse results in zero allocations, because the span operates directly on the existing string's memory instead of copying it. _Developers chasing GC-driven latency spikes compare allocation costs like these on daily.dev before optimizing hot paths._ ### What does SearchValues in .NET 8 do differently from IndexOfAny for searching characters? SearchValues, introduced in .NET 8, pre-computes a vectorized lookup table once and reuses it across all subsequent searches, whereas the standard IndexOfAny(char[]) rebuilds its lookup on every call. Declaring it as a static readonly field means the pre-computation happens once at startup, and searches then run using SIMD instructions where available, giving substantially higher throughput on large inputs. _Teams tuning .NET hot paths track SIMD-backed APIs like SearchValues on daily.dev before committing to a search strategy._ ### Why should you always return a rented array to ArrayPool in a finally block? Skipping the return call in a finally block does not leak memory outright, but it starves the pool, forcing it to keep minting fresh arrays instead of reusing already-warm ones, undermining the point of pooling. Rented arrays are also recycled rather than reset, so stale data from a previous borrower may remain; pass clearArray: true or wipe it manually if that data could be sensitive or corrupt logic. _Anyone reusing buffers with ArrayPool weighs these gotchas on daily.dev before shipping high-throughput .NET code._ ## Similar posts on daily.dev - [The Blueprint for High-Performance, Resilient .NET Applications](https://daily.dev/posts/the-blueprint-for-high-performance-resilient-net-applications-gr1arhboi) · C\# Corner · 0 upvotes · 0 comments - [15 Advanced C\# Mistakes You’re Probably Still Making](https://daily.dev/posts/15-advanced-c-mistakes-you-re-probably-still-making-ctxsuyhsf) · ITNEXT · 36 upvotes · 2 comments - [The .NET Tools Blog](https://daily.dev/posts/the-net-tools-blog-scy79z1yx) · JetBrains · 1 upvotes · 0 comments --- Tags: [#performance](https://daily.dev/tags/performance), [#.net](https://daily.dev/tags/.net) [View this post on daily.dev](https://daily.dev/posts/the-fasting-developer-memory-discipline-and-gc-awareness-in-net-5yq85h552) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"The Fasting Developer: Memory Discipline and GC Awareness in .NET","url":"https://daily.dev/posts/the-fasting-developer-memory-discipline-and-gc-awareness-in-net-5yq85h552","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/the-fasting-developer-memory-discipline-and-gc-awareness-in-net-5yq85h552"},"datePublished":"2026-07-08T12:28:46.907Z","dateModified":"2026-09-14T07:48:40.847Z","description":"A deep dive into .NET memory discipline and GC-aware coding practices. 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