4 ms·

Maybe not compress and encrypt depending on your thread model.

• noodlesUK 5y ago
  I generally think not encrypting data is a bad idea, but I can see a world where that’s a risk trade off you want to make (such as a hard drive with family photos). Why wouldn’t you want to compress it though?
  • freemint 5y ago
    There are cryptographic attacks that can exploit things being compressed. If an adversary can control some part of the files you compress together with sensitive information the size of the compressed backup provides a side channel into the content of the sensitive data.
  • jl6 5y ago
    Last time I surveyed my data, more than 99% of it was in an already compressed format (e.g. JPEG and HEVC), so compressing the backups added almost no benefit. (Now, that’s not strictly true any more for JPEGs thanks to projects like lepton and JPEG XL which can indeed compress already-compressed JPEGs losslessly).
    • KronisLV 5y ago
      > Last time I surveyed my data, more than 99% of it was in an already compressed format (e.g. JPEG and HEVC), so compressing the backups added almost no benefit. Personally, i use regular HDDs for storage of data (SSDs are out of my price point for anything but boot drives) and having fewer larger files seems to result in slightly better copying performance than having more smaller files. Though that might also have to do something with the file system and method of copying as well.
      • jl6 5y ago
        I agree, and I use tar to make backup volumes for this reason. I just don’t compress them.
  • justsomehnguy 5y ago
    Compression by itself: 1. Doesn't provide a meaningful size tradeoff for /family photos/ 2. Doesn't provide a way to recover the data if it was damaged, at best you get a notification if a decompression routine failed the verification of uncompressed data 10 years ago I had a meaningful dedup ratio, nowhadays it is cheaper for me to have another 50Gbs than bother eith a dedup