https://blog.turboawesome.win/tags/memory/ Recent content in Memory on Bits, Trades & Systems Hugo en-us Wed, 17 Aug 2022 10:03:00 +0000 https://blog.turboawesome.win/2022/08/memory-layout-in-go-structs-alignment-and-cache-performance/ Wed, 17 Aug 2022 10:03:00 +0000 https://blog.turboawesome.win/2022/08/memory-layout-in-go-structs-alignment-and-cache-performance/ Go's struct layout follows alignment rules that affect both memory consumption and cache performance. Understanding them matters more than most Go developers realise. https://blog.turboawesome.win/2016/08/heap-dumps-and-flight-recorder-diagnosing-jvm-memory-problems-in-production/ Wed, 24 Aug 2016 14:55:00 +0000 https://blog.turboawesome.win/2016/08/heap-dumps-and-flight-recorder-diagnosing-jvm-memory-problems-in-production/ Heap dumps and Java Flight Recorder are the two tools that diagnose production JVM memory problems. Understanding how to capture them without killing the service, and how to read what they tell you, is a gap in most JVM engineers' toolkits. https://blog.turboawesome.win/2015/04/memory-mapped-files-in-java-chronicle-and-the-art-of-zero-copy-i/o/ Wed, 15 Apr 2015 09:53:00 +0000 https://blog.turboawesome.win/2015/04/memory-mapped-files-in-java-chronicle-and-the-art-of-zero-copy-i/o/ Memory-mapped files let you treat disk storage as if it's RAM — the OS handles the mapping and caching transparently. Chronicle Queue uses this to give you a persistent ordered log with throughput approaching raw memory bandwidth. https://blog.turboawesome.win/2014/04/off-heap-memory-in-java-sun.misc.unsafe-and-chronicle-map/ Wed, 02 Apr 2014 10:17:00 +0000 https://blog.turboawesome.win/2014/04/off-heap-memory-in-java-sun.misc.unsafe-and-chronicle-map/ The Java heap is GC'd. Off-heap memory is not. For large data structures that don't benefit from GC management and do benefit from predictable latency, off-heap allocation via Unsafe and Chronicle Map is the right tool — if you respect its dangers. https://blog.turboawesome.win/2013/04/disruptor-deep-dive-memory-layout-cache-lines-and-false-sharing/ Tue, 09 Apr 2013 11:27:00 +0000 https://blog.turboawesome.win/2013/04/disruptor-deep-dive-memory-layout-cache-lines-and-false-sharing/ Why the Disruptor is fast is inseparable from how it's laid out in memory. A ground-up look at the cache line strategy that makes the numbers possible.