Last time I checked, their hosted databases run in dedicated VMs, which is where the real security boundary is.
Getting access to the host OS won't give you much other than some internal binaries and config.
Getting access to the host OS won't give you much other than some internal binaries and config.
I am sure Cloud SQL is far more advanced since then (9 years ago), but security in depth was something we thought about a lot. Running in a VM for each database rather than a multi-tenant system was for security more than anything else. We could have multi-tenanted just as easily implementation-wise.
This would never fly at Amazon because it would cost them a few cents to have anorher VM. Microsoft would probably not even notice the issue.
That is categorically false. Not only does Amazon's RDS do that (can't find where they say that, might have been at reinvent one year) but for other services like Fargate they used to waste way more resources due to instance single tenancy, until they adopted Firecracker: https://d1.awsstatic.com/events/reinvent/2019/CON423-R1_REPE...
But isn't this for dedicated containers and not VMs?
More broadly, based on the literature I've seen, I'd agree that GCP takes security seriously, but so does AWS and I haven't seen any good evidence to say one would be "better" than the other.
I would expect both to come up with a robust security model and as part of their defense in depth I'd expect both to enforce single tenancy at a hypervisor level any time they're running anything untrusted or which can be materially/declaratively influenced by customers (e.g. code, SQL, etc)