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SSDs have become fast, except in the cloud

(databasearchitects.blogspot.com)
589 points greghn | 1 comments | 20 Feb 24 16:59 UTC | HN request time: 0.219s | source
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pclmulqdq ◴[20 Feb 24 17:22 UTC] No.39443994[source]▶
This was a huge technical problem I worked on at Google, and is sort of fundamental to a cloud. I believe this is actually a big deal that drives peoples' technology directions.

SSDs in the cloud are attached over a network, and fundamentally have to be. The problem is that this network is so large and slow that it can't give you anywhere near the performance of a local SSD. This wasn't a problem for hard drives, which was the backing technology when a lot of these network attached storage systems were invented, because they are fundamentally slow compared to networks, but it is a problem for SSD.

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tw04 ◴[20 Feb 24 18:12 UTC] No.39444655[source]▶
>The problem is that this network is so large and slow that it can't give you anywhere near the performance of a local SSD.

*As implemented in the public cloud providers.

You can absolutely get better than local disk speeds from SAN devices and we've been doing it for decades. To do it on-prem with flash devices will require NVMe over FC or Ethernet and an appropriate storage array. Modern all-flash array performance is measured in millions of IOPS.

Will there be a slight uptick in latency? Sure, but it's well worth it for the data services and capacity of an external array for nearly every workload.

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1. folmar ◴[21 Feb 24 00:13 UTC] No.39448671[source]▶
A quick comparison of marketing slides lands you with 0.5 MOPS for FC-NVMe for Qlogic 2770 and 0.7 MOPS for PCIe Micron 9100 PRO, so the better speeds are not quite there, although spending quite a lot on server gear lands you near the performance of a workstation-grade drive from 2017.

Which is still not bad, when I was shopping around in 2018 no money could buy performance comparable to a locally-attached NVMe in a more professional/datacenter-ready form.

[1] https://media-www.micron.com/-/media/client/global/documents...

[2] https://www.marvell.com/content/dam/marvell/en/public-collat...