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SSDs have become fast, except in the cloud

(databasearchitects.blogspot.com)
589 points greghn | 2 comments | | HN request time: 0s | source
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pclmulqdq ◴[] 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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jsnell ◴[] No.39444096[source]
According to the submitted article, the numbers are from AWS instance types where the SSD is "physically attached" to the host, not about SSD-backed NAS solutions.

Also, the article isn't just about SSDs being no faster than a network. It's about SSDs being two orders of magnitude slower than datacenter networks.

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pclmulqdq ◴[] No.39444161[source]
It's because the "local" SSDs are not actually physically attached and there's a network protocol in the way.
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yolovoe ◴[] No.39446742[source]
You’re wrong. Instance local means SSD is physically attached to the droplet and is inside the server chassis, connected via PCIe.

Sourece: I work on nitro cards.

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tptacek ◴[] No.39447200[source]
"Attached to the droplet"?
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1. hipadev23 ◴[] No.39447513[source]
digitalocean squad
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2. jbnorth ◴[] No.39449627[source]
No, that’s AWS.