<story><title>πfs – A data-free filesystem</title><url>https://github.com/philipl/pifs</url></story><parent_chain></parent_chain><comment><author>adamgordonbell</author><text>I had an idea for a file transfer system based on digits of pi. You&amp;#x27;d give everybody DVDs of digits of pi (or they could calculate them themselves) , and then transfer files faster by just sending them the offset into pi.&lt;p&gt;At the time I thought it could work with a big enough bank of digits of PI on both sides. If transfer was expensive, and calculating digits was cheap then you could give everyone  an infinite supply of digits of pi and have a nearly infinite compression system.&lt;p&gt;I discovered that often the offset into pi is much larger than the data you are sending. Turns out it&amp;#x27;s an expensive way to sent things.&lt;p&gt;Also, it turns out that this area was already well understood. There are no free lunches with entropy.&lt;p&gt;But it was a fun idea to kick around.</text></comment>
<story><title>πfs – A data-free filesystem</title><url>https://github.com/philipl/pifs</url></story><parent_chain></parent_chain><comment><author>kevincox</author><text>I love the idea of this, it has certainly boggled my mind a handful of times when thinking of content-addressed storage. Obviously it can&amp;#x27;t work, there is no loophole to infinite space or compression. Entropy is a very real thing. But it did lead me down an interesting train of thought.&lt;p&gt;&amp;gt; maximise performance, we consider each individual byte of the file separately, and look it up in π.&lt;p&gt;Ok, so we store a byte and look it up in π. Now we get an offset. The exact offset will depend on the byte of course. But to simplify let&amp;#x27;s assume that π is &amp;quot;optimal&amp;quot;. We will assume that the fist 256 offsets contain the first 256 bytes.&lt;p&gt;So our offset will be in the range 0-255. Storing our offset will then take 1 byte of storage.&lt;p&gt;Oh, I have found the problem.&lt;p&gt;So yes, you can find any data in π. But storing the location of that data will on average take the same amount of space as the data itself.</text></comment>