Reading sql errorlog NUMA info

Question

So, i see the following on the sql error log:

Node configuration: node 0: CPU mask: 0x000000000000001f:0 Active CPU mask: 0x000000000000001f:0.
Node configuration: node 1: CPU mask: 0x00000000000003e0:0 Active CPU mask: 0x00000000000003e0:0.
Node configuration: node 2: CPU mask: 0x0000000000007c00:0 Active CPU mask: 0x0000000000007c00:0.
Node configuration: node 3: CPU mask: 0x00000000000f8000:0 Active CPU mask: 0x00000000000f8000:0.

Pretty much there are these 4 hex values:

0x000000000000001f:0
0x00000000000003e0:0
0x0000000000007c00:0
0x00000000000f8000:0

How does one go about getting more info from the hex values above,,, i have tried to use the windows calc app (setting - programmer), not sure if thats the way to go about it, it shows I have 4 numa nodes.. how to find which cpu's are connect to which NUMA, basically what does all the hex values above mean? Thanks.

Answer 1

Hi @SQLRocker ,

These values show the number of CPUs in the NUMA node. It will be more intuitive and clear to use SQL Server Management Studio to check NUMA nodes or the logical processors in each NUMA node(Right click on the instance > properties > processors).

For each NUMA node there is in the server there will be a line in the ERRORLOG file. The CPUs which are in the NUMA node are shown based on the values in the CPU mask and the Active CPU mask.
https://www.dcac.com/syndication/how-can-you-tell-how-many-numa-nodes-your-sql-server-has

https://bobsql.com/how-it-works-it-just-runs-faster-auto-soft-numa/

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Answer 2

Thanks Criszhan, the 2nd link there answers my question,

0x000000000000001f:0 = 0 to 4
0x00000000000003e0:0 = 5 to 9
0x0000000000007c00:0 = 10 to 14
0x00000000000f8000:0 = 15 to 19

on my 20 total logical processors server. With soft NUMA SSMS is no longer the place to see this info , as it shows me 2 NUMA nodes whereas there are 4, so don't use SSMS to glean this info, use errorlog / t-sql dmv's.