Everything I Know About SSDs
The part about filesystems is slightly incorrect.<p>&gt; The way the file system handles this is incompatible with the workings of NAND flash.<p>That&#x27;s true of most conventional filesystems, but log-structured filesystems are much more flash-friendly. That&#x27;s why there has been a resurgence of interest in them, and also why a typical flash translation layer bears a striking resemblance to a log-structured FS. There are also flash-specific filesystems.<p>&gt; to an HDD all sectors are the same.<p>This is not true because of bad blocks. Every disk has a reserve of blocks that can be remapped in place of a detected bad block, transparently, much like flash blocks are remapped. Beyond that, it&#x27;s also useful for a disk to know which blocks are not in use so it can return all zeroes without actually hitting the media. There are special flags to force media access and commands to physically zero a block, for the cases where those are needed, but often they&#x27;re not. Trim&#x2F;discard actually gets pretty complicated, especially when things like RAID and virtual block devices are involved.