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On 02/01/2020 19:12, Rich Freeman wrote: |
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> For reads they're completely normal. For sequential writes to unused |
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> space they're completely normal. For random writes or overwrites they |
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> are significantly different from traditional hard drives. |
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That's why the "S" stands for "shingled" (which means "overlapped", |
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think of a shingled roof - which is your normal overlapping tile jobbie). |
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The point of a shingled drive is that it has a narrow read head - let's |
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call it one unit wide. But a write head is larger, lets call it three |
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units wide. If each track is one unit wide - the correct size to be read |
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- then writing a track will destroy two tracks. |
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So the write head lays down data in concentric rings, and CAN'T |
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overwrite data - it has to wipe everything and rewrite it. So as |
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mentioned before you really do not want these drives for random writes - |
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think of them as a bit like a random-write tape drive ie you can get |
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away with it but you're better off not trying. |
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And yes - the 8TB capacity gave it away - I think the largest "normal" |
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drives available are 4TB at present ... anything bigger must be shingled. |
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Cheers, |
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Wol |