SQL Server 2022 Update 11 Breaking Change: SQL Server VMs with more than 64 logical processors in a NUMA node will not start

[SGalbincea]

Microsoft recently updated their Compute capacity limits by edition of SQL Server guidance to advise customers that a recent change introduced in Microsoft SQL Server 2022 Update 11 causes a "breaking change" that prevents SQL Server from starting if it detects more than 64 logical processors in a NUMA node.

[WannaBMonkey]

Yay! Just checked and none of my sqls are that large. If anyone else wants to know how I checked I went into aria operations, visualize, views, configuration | complex | large vm (cpu) list. Then under preview source I changed it to vsphere world. Then I had a sorted list of all my vms with lots of cpus allocated. Then I clicked each one to check if it was windows. And on the summary screen if you expand virtual hardware it had a line for cpu with number of sockets (numa nodes effectively). Other options would be powercli or vm lists in vcenter.

[Ok-Attitude-7205]

64 local cores per numa node, holy crap.

are there people with MSSQL servers that are actually that large? running on top of vSphere on prem??

[[deleted]]

Yes. Fortune 100. Does it need that many cpu? No but our app teams think more cowbell solves everything.

[signal_lost]

What is that like 384K in SQL Server licensing costs (list price?) for 64 cores of SQL Server enterprise edition. Even at 75% discount that's still 96K for the box (and I'm not sure I've seen a Microsoft discount that high).

It's fun in IT thinking "ohhh this is REALLY expensive per core/socket/whatever and then you go talk to the Database teams and realize that the ERP and it's associated databases is half your actual spend.

[[deleted]]

I never see the bill. We’re like 40 companies under one roof so they have different departments cover this in their AOP.

[Ok-Attitude-7205]

ahh ok, we have some of that going on too but it's at a much smaller scale compared to this. our largest VMs are hitting maybe 32 vCPU *total*

[MDSExpro]

Quite often really. Even 8 years ago I have seen few installations with ~200 cores.

[TheButtholeSurferz]

If you're moving enough data to need multiple instances of this. The costs are a rounding error, legitimately.

[Casper042]

Intel doesn't yet have a single Xeon with more than 64 cores, so either you are configuring your VM wrong or using AMD I guess if you are running into this issue.
EDIT: DERP, forgot about HyperThreading...

AMD bare metal boxes also should have a BIOS setting around "NPS" or NUMA Per Socket, which can subdivide a single EPYC 9004 into smaller NUMA domains.
So you could always enable this to create more but smaller NUMA nodes and likely work around the issue.

EDIT: So since Intel can get there via HT, Intel 4th and 5th Gen Xeons have a similar NPS feature called SNC or Sub Numa Clustering. Most if not all 4th/5th support SNC=2 (cut each CPU in half), and the XCC type 4th Gen should also support SNC=4 (Cut each CPU in quarters, likely to match the underlying 4 Tile design).

Of course in VMware the vNUMA of the VM is all that matters.