It&#x27;s also really useful if you have a lot of numerical data streaming in that you want to store and use at a later date. CERN results I&#x27;m sure use something similar to HDF5, nearly all of HFT algo trading uses HDF5 for securities they are going to explore down the road but don&#x27;t want to waste KDB+ licenses on, Google File System&#x27;s chunking scheme seems to be somewhat similar to it as well. <i>_&quot;Third, most files are mutated by appending new data rather than overwriting existing data. ... Once written, the files are only read, and often only sequentially.&quot;_</i> [1] _That_ is the use case for HDF5. The problem is this guy tried to slam a circular peg into a square hole. I&#x27;m in no way an apologist for HDF5 but his complaints are terribly vague. &quot;Limited support for parallel access&quot; Then you go read the source[2] and and see GIL complaints abound. And again, this was meant for an append-only situation where you shouldn&#x27;t even have to acquire a lock in the first place since there&#x27;s no contention possibility! &quot;Impossibility to explore datasets with standard Unix&#x2F;Windows tools&quot; right, but there are plenty of Java tools that perform quite well, even with a cold JVM. &quot;Opacity of the development and slow reactivity of the development team.&quot; AFAIK it&#x27;s an open-source project, this complaint is valid if you&#x27;re paying a vendor fees for a product and have a support plan with an SLA, and it&#x27;s not valid in the least otherwise. &quot;High risks of data corruption&quot; I&#x27;ve never once seen this happen when HDF5 was properly used, though I&#x27;d love to see a pdb dump of the state his program when that occurred. Open offer - I&#x27;ll fix that bug if it&#x27;s a fault with the C lib you&#x27;re FFI&#x27;ing with.<p>edit: oh, the Java tooling was already mentioned.<p>[1] <a href="http:&#x2F;&#x2F;static.googleusercontent.com&#x2F;media&#x2F;research.google.com&#x2F;en&#x2F;&#x2F;archive&#x2F;gfs-sosp2003.pdf" rel="nofollow">http:&#x2F;&#x2F;static.googleusercontent.com&#x2F;media&#x2F;research.google.co...</a> 
[2] 
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