https://blog.turboawesome.win/tags/chronicle/ Recent content in Chronicle on Bits, Trades & Systems Hugo en-us 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/ 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/2015/01/chronicle-queue-vs-kafka-choosing-a-persistent-journal-at-nanosecond-scale/ Wed, 21 Jan 2015 10:44:00 +0000 https://blog.turboawesome.win/2015/01/chronicle-queue-vs-kafka-choosing-a-persistent-journal-at-nanosecond-scale/ Both Chronicle Queue and Kafka provide persistent, ordered message logs. Their performance profiles, operational models, and use cases are almost completely different. 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/2013/09/java-chronicle-off-heap-persistence-without-serialisation-overhead/ Thu, 05 Sep 2013 14:22:00 +0000 https://blog.turboawesome.win/2013/09/java-chronicle-off-heap-persistence-without-serialisation-overhead/ Chronicle Map and Chronicle Queue use memory-mapped files to give you persistent storage that doesn't touch the GC heap. Here's how we used it for trade journaling at microsecond latency.