Experimenting with btrfs in production.

  data_storage geek_porn hardware howto leandra btrfs libreops exocortex

EDIT - 20201206 @ 2216 UTC-7 - Added how to remove a hard drive and replace it with a bigger one to upgrade. EDIT - 20200311 @ 1859 UTC-7 - Added how to replace a dead hard drive in a btrfs pool.

EDIT - 20191104 @ 2057 UTC-7 - Figured out how long it takes to scrub 40TB of disk space.  Also did a couple of experiments with rebalancing btrfs and monitored how long it took.

A couple of weeks ago while working on Leandra I started feeling more and more dissatisfied with how I had her storage array set up.  I had a bunch of 4TB hard drives …

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Genetic jiggery-pokery.

  genetics genetic_engineering information dna structure crispr data_storage computation processing

It's long been known that DNA encodes information in a four-bit pattern which can be read and processed like any other bitstream. Four different nucleotides, paired two by two, arranged in one of two configurations side by side by side in a long string of letters, many times longer than the size of the cell containing the full DNA strand. Every cell in every single lifeform contains the same DNA sequence, regardless of what the cell actually does. So how, many have asked, does a cell know if it should help produce hair, or skin, or pigments, or something else …

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Xeno-nucleic acids and biological computation.

  biotech data_storage dna encoding information synthetic_biology xna

Disclaimer: I am not a geneticist. If I got some bits wrong let me know and I'll correct my post.

It is a basic fact that DNA (deoxyribonucleic acid) is the fundamental mechanism of complex life on this planet. DNA encodes the structure of every protein used by complex life in much the same way that a Turing machine would use a paper or magnetic tape to store data. The codon (triplet of base pairs) ATG means that the amino acid methionine goes first, the codon TCT means that serine goes next, then histidine, and so on and so forth …

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Holographic data storage

  computers data_storage holography information optics

Physicists at the University of Rochester have made a breakthrough in data storage technology, namely, they've been able to store an entire image within a single photon using holographic techniques. An image of the UofR logo was cut into a stencil and a beam of laser light was passed through a beam splitter (classic holographic imaging technique); then a single photon from that beam was passed through the cut out portion of the stencil. Due to the nature of quantum mechanics, that photon passed through every region of the cut away part of the stencil (or at least, that's how …

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