Clojure: Java FileSystem Primitives for Implementing Database Persistence -

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context

this purely education purposes. want write primitive database. focus not on performance; principles behind databases. have material on locking / mutexes / transactions. know nothing writing disk / guaranteeing persistence in unexpected hardware (say power) failures.

in order have proper recovery / persistence, need guarantees when writing files disk.

question:

for above purposes, types of file primitives (guarantees file written disk? leaving file open , appending log?) need? jvm offer?

thanks!

it's huge area talk because of many layers of abstraction surrounding discs these days, though jvm's perspective pretty depend on fsync write bits disc once call fsync depend on these bits being on disc. rest built on this.


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