SQL is consuming lot of RAM due to buffer pool can anyone help how we can clear the buffer pool automatically

SQL Server Administration
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SQL is consuming lot of RAM due to buffer pool can anyone help how we can clear the buffer pool automatically

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This is precisely what SQL Server is designed to do, and how it operates best. More memory, and more data in buffer pool, improves performance substantially.

If your SQL Server is contending with other services on the same machine, move those other services. SQL Server should be the only major service on the box.

If that's not possible, you can set a max memory limit via sp_configure:

More details and recommendations here:

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Hi Robert,

Thanks for your reply.

We have tried setting up the max memory limit via sp_configure but still, we are facing the same issue.
RAM is getting consumed to 80% so we need to restart the SQL service which eventually I suppose clears the buffer pool as well and then the RAM usage goes down to 25% but after every 3 to 4 hours RAM again shoots up to 80% and we need to restart the service again.
Aint there any query that can clear the buffer pool automatically at regular intervals?
Again is it a good option to clear the buffer pool or to restart the SQL service when the users are working live?

your kind response will be helpful.

Regards,
Vishal S

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Why do you feel that it is a problem for SQL Server to use 80% of the available RAM? If anything else running on the operating system needs more memory, the OS can handle it by paging or swapping.

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It is not a good idea to clear the buffer pool - nor is it a good idea to restart the SQL service when the users are working.

All you are doing is causing interruptions and performance issues for your customers. The fact that SQL Server is taking up memory on a server isn't a problem - that is what it is supposed to do.

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Q Oh Yes I anticipated that but if I do not restart the service the front-end application which is using SQL db creates duplicate records.

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That is quite a problem!

What leads you to believe this duplicate records problem is related to the amount of buffer pool space SQL Server is using?

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In SQL Server, the buffer pool is used to store data pages read from the disk, improving access speed to the data. In some cases, you may want to manually or automatically clear the buffer pool to release memory. However, generally speaking, SQL Server typically manages the buffer pool automatically, and manually clearing the buffer pool can lead to performance issues, as SQL Server will need to reload data pages.

If your requirement is to temporarily release buffer pool memory, you can do so using one of the following methods:

  1. Using DBCC command: The DBCC DROPCLEANBUFFERS command can be used to clear all data pages from the buffer pool. Note that this is temporary, and the next time a query needs to access the data, SQL Server will reload it from disk.

    DBCC DROPCLEANBUFFERS;

  2. Using ALTER SERVER CONFIGURATION: If you are using SQL Server 2012 and later versions, you can use the ALTER SERVER CONFIGURATION command to more finely manage the buffer pool.

    ALTER SERVER CONFIGURATION SET MEMORY_CLEAR_PROCEDURE 'ALL';

    This executes a procedure within the SQL Server process to clear the system buffers, including the plan cache and the procedure cache. This is also a temporary operation.

It's important to note that these operations may have a negative impact on SQL Server's performance as it needs to reload data. Therefore, in regular operations, frequent manual clearing of the buffer pool is not recommended. If you find SQL Server occupying a large amount of memory for an extended period, consider adjusting the memory settings of SQL Server to suit the needs of the system.

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I am not sure when the RAM is utilizing max memory we can see buffer pool is a major contributor.

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Just want to ask if restarting the SQL service also clears buffer pool memory.