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I hope this makes its way into ReFS or some other Windows filesystem. A friend who used to work on the NTFS team told me ReFS was B-tree based, which disappointed me as B-Trees are ill suited to SSDs.

It was almost like MS completely missed the technology shift due to their glacial release cycles. But maybe I was wrong.

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Since when are B-Trees ill-suited to SSDs? The big idea behind B-Trees is to store pages of keys, and SSDs still operate on pages.

The key feature of B+Trees is that they are optimized to allow sequential scans through the index - I suppose SSDs don't "need" the sequential scan property, but it doesn't hurt, and pragmatically would still reduce the number of disk reads required to perform a scan of the index.

B-Trees are all fine and nice, and perfectly adequate for SSDs, but log structured filesystems provide better wear leveling and garbage collection, even with TRIM support.

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