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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: 0.774s | 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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_Rabs_ ◴[20 Feb 24 17:24 UTC] No.39444028[source]▶
So much of this. The amount of times I've seen someone complain about slow DB performance when they're trying to connect to it from a different VPC, and bottlenecking themselves to 100Mbits is stupidly high.

Literally depending on where things are in a data center... If you're looking for closely coupled and on a 10G line on the same switch, going to the same server rack. I bet you performance will be so much more consistent.

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bugbuddy ◴[20 Feb 24 17:30 UTC] No.39444090[source]▶
Aren’t 10G and 100G connections standard nowadays in data centers? Heck, I thought they were standard 10 years ago.
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1. KaiserPro ◴[20 Feb 24 20:01 UTC] No.39446155[source]▶
Yes, but you have to think about contention. Whilst the Top of rack might have 2x400 gig links to the core, thats shared with the entire rack, and all the other machines trying to shout at the core switching infra.

Then stuff goes away, or route congested, etc, etc, etc.