How to know SQL Server Memory Utilization

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How to know SQL Server Memory Utilization

vinod.saraswat

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Points: 2395
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September 24, 2012 at 5:22 am

#282034

Hi All,
We have SQL 2008R2 Standard Ed.(64 bit) installed on Windows 2008 R2. Physical RAM on Server is 48GB.
We have set SQL maximum memory to 35GB.
Is there any way to know about how much memory is getting utilized by the SQL server out of 35GB.
Below are some details
Target Server Memory (KB) = 36700160
Total Server Memory (KB) = 36700160
Memory from task manager in MB
Total49142
Cached2648
Available8222
Free5624
sqlsvr.exe 38456316 (in KB)
Which information is correct how do I calculate memory usage for SQL out of 35GB (35840MB)

Viewing 7 posts - 1 through 6 (of 6 total)

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Orlando Colamatteo SSC Guru Points: 182279 More actions · Answer 1

Amount of memory being used for the buffer pool:

SELECT CAST((bpool_committed * 8) / (1024.0 * 1024.0) AS DECIMAL(20, 2)) AS BufferPoolCommittedMemoryGB

FROM sys.dm_os_sys_info;

There are no special teachers of virtue, because virtue is taught by the whole community.
--Plato

vinod.saraswat SSCrazy Points: 2395 More actions · Answer 2

Hi,

Thanks for your reply.

Out put of your query is 35GB which I have set for max server memory.

I got some query from blog of SSC only which give the utilization of buffer.

With CTE_BP(DatabaseName, BufferSizeInMB )

as

(

SELECT

case when DB_NAME(b.database_id) is null then 'Resource DB' else DB_NAME(b.database_id) end AS database_name

,(cast(COUNT(*) as decimal(20,2)) * 8192.00) / (1024.00 * 1024) AS buffer_count_MB

FROM sys.dm_os_buffer_descriptors AS b

GROUP BY b.database_id

)

select * from CTE_BP order by BufferSizeInMB desc

Here is the out put memory in MB

db1 18035.23438

db2 5483.632813

tempdb2719.28125

db3 1926.796875

db4 718.359375

msdb 98.3828125

Resource DB 18.625

master0.9609375

model 0.359375

If I some up this 29001.63281 MB. So now what is the difference between bpool_commited memory & buffer descriptor memory. Can I some how know the details of 35GB utilization same like buffer descriptor memory so that I can properly justify the 35GB as the max server memory setting.

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 3

Your query returns the size of the data cache, which is one component of the buffer pool. There are a lot of other caches including the plan cache also within the buffer pool.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

vinod.saraswat SSCrazy Points: 2395 More actions · Answer 4

Thanks for the reply Gail.

so bpool_commited is the only consolidated way to describe the memory usage out of max server memory setting.

Any reference to calculate memory of all component will be helpful..

SQL Show SSCertifiable Points: 6143 More actions · Answer 5

select Type, SUM(single_pages_kb)/(1024.00) SingleP_MB

, SUM(Multi_pages_kb)/(1024.00) MultiP_MB

, SUM(virtual_memory_committed_kb)/(1024.00) VirtualP_MB

, SUM(shared_memory_committed_kb)/(1024.00) SharedP_MB

, SUM(awe_allocated_Kb)/(1024.00) AWEp_MB From sys.dm_os_memory_clerks

Group by type

try this..

vinod.saraswat SSCrazy Points: 2395 More actions · Answer 6

Thanks for the reply.

I have attached out put of this query in excel format.

So then SQL max server memory = Sum(SingleP_MB)+Sum(MultiP_MB)+data cache memory.

Please correct if I am wrong.

Thanks again to all for all great efforts.