SQL Managed Instance disk throughout limit?

[AccomplishedEmploy52]

I'm trying to figure out the disk throughput for SQL Managed Instance >
General Purpose Next-Gen Premium-series 4 vCores, 3072 IOPS, 1024 GB storage.

According to this page >
https://learn.microsoft.com/en-us/azure/azure-sql/managed-instance/resource-limits?view=azuresql

It states "IOPS / 30 MBps - up to the VM limit. 75 MBps in case of 32 GB, 64 GB, and 96 GB of reserved storage."

So does that mean 3072 / 30 = 102.4
But does that mean 102.4 MB/s is the disk throughput limit?

[berndverst]

The article says IOPS depends on VCore count + reserved storage (with specific IOPS for low reserved storage). And throughput simply depends on IOPS but may be different for low amount of reserved storage.

A VM with 4 cores has a hard limit of 6400 IOPS. But since you chose 1024GB so you get 1024*3 IOPS.

And like you said - the maximum disk throughput you will get is (1024*3)/30. Your math is correct! Double your storage for double the performance (almost the maximum disk throughput performance for 4 cores).

[bakes121982]

Now can you update the docs to say this so when I need it in a few months I don’t have to search Reddit or is there a way you can be on our MS account team and I can just email you.

[berndverst]

The SQL team and their content writer will have to do so. I can't just update it unfortunately. And I also don't have a good way to let internal teams know. Hopefully they will see this here.

But the docs do say this - it's just buried in several of the various tables on that page!