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<td class="text-paragraph-pattern-container mobile-resize-text " style="padding: 0px; border-collapse: collapse; padding: 0 0 10px 0"> <p style="margin: 10px 0 0 0; margin-top: 0">I think maybe my comment about the math wasn't very clear. You get 64K "leaf" directories <b>in total</b> which could contain files. But not 64K in a single directory. You have (potentially) 256 1st level dirs. Then in <b>each</b> of those you have (potentially) 256 2nd level dirs. So the max dirs you have in an 'ls' for example would be 256.</p> <p style="margin: 10px 0 0 0">(I say "potentially" because there is no need to create them all up front. They can be created lazily only when needed to store a file that hashes to that path).</p> <p style="margin: 10px 0 0 0">So assuming an (unlikely) perfect distribution of the hashed files, if you had say 64K files, you'd have only 1 file in each 2nd level dir. If you had 1 million files, it would be 1,000,000/65,536 = ~ 15 files per directory.</p> <p style="margin: 10px 0 0 0">So having talked that out...maybe we don't need 2 levels - maybe 1 level of 256 is enough? That would distribute 100,000 files as roughly 390 files per dir.</p> <p style="margin: 10px 0 0 0">I guess it all depends on what size dataset we think is actually realistic to expect.</p> <p style="margin: 10px 0 0 0">The other thing I personally don't know is the characteristics of the SHA algorithms when you just take some of the bits and not all of them. I.e. in reality how "distributed" are the first 8 bits or the first 16 bits? The whole hash value is supposed to be relatively distributed, but not sure about mathematical properties of a subset of the bits. Seems like it would be, but this is not my area...</p> </td>
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