Comments on: SQL Server Diagnostic Information Queries for February 2017

By: Glenn Berry

Glenn Berry — Mon, 15 May 2017 19:45:41 +0000

In reply to Margaret. The CPU Utilization History query shows "System Idle Process", which the available CPU for the entire system, in one minute snapshots over the past 255 minutes.

By: Margaret

Margaret — Mon, 15 May 2017 19:23:49 +0000

Hi Glenn — Re CPU by db. The amount given is the Percent of CPU per database out of the total USED CPU, not the total AVAILABLE CPU — if I am reading the formula correctly. Do you address the percent of available cpu with your queries anywhere?

By: Glenn Berry

Glenn Berry — Tue, 21 Feb 2017 23:01:37 +0000

In reply to 7gartner.

I have never seen that myself, but I have gotten some isolated reports of that happening. Unfortunately, the sys.dm_os_ring_buffers DMV is poorly documented and semi-deprecated.
https://msdn.microsoft.com/en-us/library/ms176083.aspx?f=255&MSPPError=-2147217396

By: 7gartner

7gartner — Tue, 21 Feb 2017 22:57:18 +0000

Hi Glenn,
with Query 40 I sometimes will see a negative CPU usage calculated for Other Process CPU Utilization because SQL Server CPU + System Idle is somehow greater than 100. Have you run into this at all?

This has occurred on my high core-count systems (E5-2660 v3). I have yet to see this occur on my smaller systems with 8-12 cores.

-jim

By: David Turpin

David Turpin — Thu, 09 Feb 2017 19:57:03 +0000

Thanks Glenn. I guess I jump right to the queries and never read the header blocks. I’ve been using these queries for a long time, but have to admit I didn’t fully appreciate the ramifications of some of them. No doubt your classes on PluralSight will fill in the gaps…

These queries are a great service to the SQL community.