[morei]

That's not really how it's done.

RS is normally used as erasure code: It's used when writing (to compute code blocks), and when reading _only when data is missing_. Checksums are used to detect corrupt data, which is then treated as missing and RS used to reconstruct it. Using RS to detect/correct corrupt data is very inefficient.

Checksums are also normally free (CRC + memcpy on most modern CPUs runs in the same time that memcpy does: it's entirely memory bound).

The generation of code blocks is also fairly cheap: Certainly no large matrix multiplications! This is because the erasure code generally only spans a small number of blocks (e.g. 10 data blocks), so every code byte is only dependent on 10 data bytes. The math for this is reasonably simple, and further simplified with some reasonable sized look-up tables.

That's not to say that there is no CPU needed, but it's really not all that much, certainly nothing that needs acceleration support.