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Buffer Cache

Buffer cache is a part of the buffer pool which is also referred to as the data cache. The buffer cache is responsible for holding the data pages in memory which are frequently accessed by Sql Server. Alternatively data pages are read from the disk which causes high IO operations.

How do you clean the buffer cache without restarting the server ? Following are two DBCC command that could be used to clear the buffer cache.

  • DBCC DropCleanBuffers
    This DBCC command clears the entire buffer cache for a give sql server instance
  • DBCC FlushProcinDB (DBID)
    The DBCC command clears the buffer cache for the given database


Example 1

This shows the buffer cache can be cleaned using the


DBCC FLUSHPROCINDB

SELECT * FROM sys.syscacheobjects where dbid = db_id('ADVENTUREWORKS')

GO

DBCC FLUSHPROCINDB(12)

GO

SELECT * FROM sys.syscacheobjects where dbid = db_id('ADVENTUREWORKS')

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