Trim and unallocated space

Have you ever heard that solid-state drives destroy evidence? Let’s revisit the facts before going further.

When first solid-state drives appeared, there was no Trim command. There was no easy way for a drive to reclaim unused blocks of user data (i.e., data exposed to a host as drive contents) for the wear-leveling process.

To mitigate this problem, manufacturers did a clever trick: they began producing file-system-aware solid state drives!

Some articles deny the existence of such a trick, but the truth is that some ancient solid-state drives were capable of parsing a partition table and an NTFS file system to locate unallocated (free) clusters and reclaim their blocks for the wear-leveling process (thus, wiping remnant data in these clusters).

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