Questions tagged [buffer-pool]
A place in system memory that is used for caching table and index data pages as they are modified or read from disk.
114 questions
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Is MEMORYCLERK_SQLBUFFERPOOL how much RAM I'm actually using or how much I could be using?
This lovely query of Glenn Berry's lets you see what is in your buffer pool.
SELECT fg.name AS [Filegroup Name], SCHEMA_NAME(o.Schema_ID) AS [Schema Name],
OBJECT_NAME(p.[object_id]) AS [Object Name], ...
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Mysql huge table vs small ram allocation
We have a percona mysql database where one of the table which is touching almost 26.8Gb in size. The server is just 4Gb but its specifically only hosting mysql. Now when I am trying to run a simple ...
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OS memory usage is high, but MS Sql server has plenty of free memory
On sql server 2019, I occasionally get "Physical Memory pressure" alert.
When I check the memory usage, I get two different cases.
There is a large memory in free pages.
Can anyone explain ...
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Is sys.dm_os_memory_clerks a good source to use when setting max server memory (MB)?
According to sys.dm_os_memory_clerks, the total RAM usage of my server was 30 GB. Using this information, I set max server memory (MB) to 31,000. I was shocked to then see sys.dm_os_memory_clerks ...
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Problem with saving data SQL
For some time now I have had a problem with saving data in the database.
The problem is that after a sudden shutdown of the server, the data that was sent a minute earlier from the application was not ...
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Do stolen pages (as in sys.dm_os_performance_counters) report anything that sys.dm_os_memory_clerks does not?
I have been under the misconception that SELECT * FROM sys.dm_os_performance_counters WHERE counter_name LIKE 'Stolen Server Memory%'; shows how much memory the OS is stealing from SQL Server. The ...
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Is Monitoring Buffer Pages Too Noisy To Be Useful?
I quite like dbatools, so I gave Get-DbaDbMemoryUsage (docs here) a try on my production SQL Server 2019 server. Specifically, I ran this
Get-DbaDbMemoryUsage -SqlInstance [MyProdServer] -...
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76% of the RAM usage on my server is TEXT_MIX_PAGE in tempdb. What does this indicate?
I quite like dbatools, so I gave Get-DbaDbMemoryUsage (docs here) a try on my test SQL Server 2019 server. Specifically, I ran this
Get-DbaDbMemoryUsage -SqlInstance [MyServer] -IncludeSystemDbs |
...
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Trying to understand the buffer pool usage - actual usage greatly exceeds the total from
I am reviewing the buffer pool size and usage on a setup that was recently moved to a machine with more RAM (new machine has 256 GiB). MySQL server version is 5.7.42.
The total data size in the DB (...
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Why does MySQL puts ANALYZE queries into `System Lock` state, when there is intense I/O
On MySQL 8.0.33, I'm experiencing a form of contention (reproduced on multiple instances) that is not explained by the documentation.
As example:
I boot an instance
on a console client, I invoke a ...
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View memory usage by database on an SQL server
My team (no DBAs in the team) is responsible for a database hosted on an SQL server with multiple other databases used by other areas of the business. Memory usage has recently been spiking to 100% on ...
David G
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Buffer Pool caching in Sql clarification
I might sound a little naive to ask this question but I couldn’t find out the answer anywhere.
So my understanding is that the buffer in a sql db maintains disk pages in cache so that when a query ...
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How to identify if my innodb buffer pool is choking ? (and should i increase it ?)
We have a mysql box where i do rigorous scans/aggregations every few minutes (~ 35GB of data). Innodb buffer pool is ~ 1.5GB.
Off late i have started noticing a few latent queries, where the 'read ...
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What is the Rule of thumb for alerting on`mysql.innodb.buffer_pool_reads / mysql.innodb.buffer_pool_read_requests`?
Is there a rule of thumb for monitoring mysql.innodb.buffer_pool_reads / mysql.innodb.buffer_pool_read_requests?
I am using the following formula, but I'm starting to think it's too sensitive.
(mysql....
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SQL Server - Find Memory ALLOCATED vs. Memory ACTUALLY USED
I want to find average Memory USED per day.
SQL server caches as much data as possible in RAM (Buffer Cache) - this is ALLOCATED RAM
But how much of this data does it actually read subsequently - this ...
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