Max Server Memory configured but it increases more of its configuration

Question

Following a previous post I've written, I've configured my server with the following parameters:

I put 22497 as MAx Server Memory, disable AWE, since it runs in 64 bit environment and it's a production server.

During a reboot, it starts from the min configuration, and slowly increase memory consumption until almost midnight that reaches the max memory configuration.

Until then if I monitor memory consumption, the task manager reports that memory increases to 25 GB of RAM. Yesterday we removed AWE, reboot the instance, and it started slowly increasing memory Until around 17:00pm , it was using almost 25.2 GB of RAM:

Today after a reboot, it is now using 11GB.

I now, that in a previous post said this memory consumption is "Normal Behaviour" of SQL Server, but why it suddenly use more of the max memory I set as maximum? UPDATE 2021-03-31:

As for Today March 31, 2021 08:09AM, my server is using 25.3 GB of RAM:

Using Aleksey Script This are the numbers SQL Reports is using:

Resource Monitor says SQL Server IS using all the RAM:

Yesterday at 17:00 it was using 13 GB

And this is the behaviour of the server, That's why I'm asking if this is normal or not, what is making the server use 25.3 GB if it's limit should be 22.5 GB (rounded per my calculations). This is the issue.

I know Microsofts literature says a lot of stuff, but I haven't get a clue of why this behaviour, I've already check Stored Procedures, Indexes, Jobs, etc.. and I don't see what is making the SQL Server use more of the assigned maximum server memory.

I disabled AWE, since this instance is running in a Virtual Machine in Hyper V, 64 bit Environment, (Windows 2008 R2 64 Bit, Microsoft SQL Server 2008 R2 (RTM) - 10.50.1600.1 (X64) Apr 2 2010 15:48:46 Copyright (c) Microsoft Corporation Enterprise Edition (64-bit) on Windows NT 6.1 (Build 7601: Service Pack 1) (Hypervisor) and I can't figure what's going on with this behaviour.

Answer 1

MAX SERVER MEMORY worked a little differently before SQL Server 2012:

Starting with SQL Server 2012, Multi-Page allocations and CLR allocations are also included in memory limits that are controlled by max server memory (MB) and min server memory (MB).

Memory configuration and sizing considerations in SQL Server 2012 and later versions

Answer 2

When Total used memory reaches over 25 GB of RAM again, you can check how much SQL Server consuming RAM, using Windows Resource Monitor (Memory tab)

It is also possible that some other application consumes your memory, Resource Monitor can help to confirm that (or otherwise prove SQL Server overblowns the limits)

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Also, check how much memory SQL Server is currently using, try stored procedure "MemoryManagerInfo"

https://github.com/aleksey-vitsko/Database-Administrator-Tools/blob/master/Memory%20-%20MemoryManagerInfo.sql

Deploy it to any user database and run. Post the output to the question
It will be similar to below picture:

This SP will help to confirm or disprove that your SQL Server is consuming over 22497 MB
Look for "Target Server Memory" and "Total Server Memory" values

Update:

Based on screenshots you added today to the question - 1) Windows Task Manager (what you posted is not Resource Monitor) says your SQL Server is using 23,281,112 KB which is = 22.2 GB

Not 25.3 GB ! Other 3.1 GB are just other applications

If you worry about your server starving off memory, reduce Max Server Memory in SQL Server to a lower number (20 GB, 19 GB, 18 GB etc.)

Resource Monitor