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Optical PCIe 7.0 connection hits 128 GT/s

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204 points WithinReason | 2 comments | 17 Jun 24 11:42 UTC | HN request time: 0s | source
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taneq ◴[17 Jun 24 23:07 UTC] No.40712220[source]▶
GT/s = gigatranfers per second.
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8n4vidtmkvmk ◴[17 Jun 24 23:42 UTC] No.40712523[source]▶
What's a transfer? That like a packet or a single bit?
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Arnavion ◴[17 Jun 24 23:51 UTC] No.40712584[source]▶
One bit, but it's a bit of the underlying signal layer which has a 1-2% redundancy over the actual data. PCIe 2.0 and earlier encode 8b data in 10b signal. 3.0 to 5.0 encode 128b data in 130b signal. 6.0 and 7.0 do a more complicated thing: https://pcisig.com/blog/pcie%C2%AE-60-specification-webinar-...

Also the speed is per lane, eg an x8 slot / port / device is called that because it has 8 lanes, which all transfer in parallel.

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yjftsjthsd-h ◴[17 Jun 24 23:58 UTC] No.40712626[source]▶
Edit: Nope, I misread. As reply notes, 16GB/s/lane.

So... That's about 16 terabytes per second per lane. AKA more bandwidth than I can imagine any use for, though I'm sure we will find ways to take advantage...

(Seriously, that's enough to move 16 largish laptop drives every second, on a single lane.)

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1. Arnavion ◴[18 Jun 24 00:04 UTC] No.40712668[source]▶
>So... That's about 16 terabytes per second per lane.

If you assume 1T/s = 1b/s, 128GT/s is 128Gb/s = 16GB/s, not 16TB/s

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2. yjftsjthsd-h ◴[18 Jun 24 00:27 UTC] No.40712786[source]▶
Oops, yep, I misread that. Thanks for the correction