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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: 0.399s | 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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mkoubaa ◴[20 Feb 24 17:30 UTC] No.39444085[source]▶
Dumb question. Why does the network have to be slow? If the SSDs are two feet away from the motherboard and there's an optical connection to it, shouldn't it be fast? Are data centers putting SSDs super far away from motherboards?
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1. supriyo-biswas ◴[20 Feb 24 18:01 UTC] No.39444510[source]▶
It’s not the network being slow, but dividing the available network bandwidth amongst all users, while also distributing the written data to multiple nodes reliably so that one tenant doesn’t hog resources is quite challenging. The pricing structure is meant to control resource usage; a discussion of the exact prices and how much profit AWS or any other cloud provider makes is a separate discussion.