duckdb::BufferManager Class Reference

Public Member Functions
virtual shared_ptr< BlockHandle >	AllocateTemporaryMemory (MemoryTag tag, idx_t block_size, bool can_destroy=true)=0
	Allocate temporary memory of size block_size.
virtual shared_ptr< BlockHandle >	AllocateMemory (MemoryTag tag, BlockManager *block_manager, bool can_destroy=true)=0
virtual BufferHandle	Allocate (MemoryTag tag, idx_t block_size, bool can_destroy=true)=0
	Allocate (temporary) memory of size block_size, and pin it.
virtual BufferHandle	Allocate (MemoryTag tag, BlockManager *block_manager, bool can_destroy=true)=0
	Allocate block-based memory and pin it.
virtual BufferHandle	Pin (shared_ptr< BlockHandle > &handle)=0
	Pin a block handle.
virtual BufferHandle	Pin (const QueryContext &context, shared_ptr< BlockHandle > &handle)=0
virtual void	Prefetch (vector< shared_ptr< BlockHandle > > &handles)=0
virtual void	Unpin (shared_ptr< BlockHandle > &handle)=0
	Unpin a block handle.
virtual idx_t	GetUsedMemory () const =0
	Returns the currently allocated memory.
virtual idx_t	GetMaxMemory () const =0
	Returns the maximum available memory.
virtual idx_t	GetUsedSwap () const =0
	Returns the currently used swap space.
virtual optional_idx	GetMaxSwap () const =0
	Returns the maximum swap space that can be used.
virtual idx_t	GetBlockAllocSize () const =0
	Returns the block allocation size for buffer-managed blocks.
virtual idx_t	GetBlockSize () const =0
	Returns the block size for buffer-managed blocks.
virtual idx_t	GetQueryMaxMemory () const =0
	Returns the maximum available memory for a given query.
virtual shared_ptr< BlockHandle >	RegisterTransientMemory (const idx_t size, BlockManager &block_manager)
	Returns a newly registered block of transient memory.
virtual shared_ptr< BlockHandle >	RegisterSmallMemory (const idx_t size)
	Returns a newly registered block of memory that is smaller than the block size setting.
virtual shared_ptr< BlockHandle >	RegisterSmallMemory (MemoryTag tag, const idx_t size)
	Returns a newly registered block of memory that is smaller than the block size setting and has a memory tag.
virtual DUCKDB_API Allocator &	GetBufferAllocator ()
	Get the buffer allocator.
virtual DUCKDB_API void	ReserveMemory (idx_t size)
	Reserve memory.
virtual DUCKDB_API void	FreeReservedMemory (idx_t size)
	Free reserved memory.
virtual vector< MemoryInformation >	GetMemoryUsageInfo () const =0
	GetMemoryUsageInfo returns MemoryInformation for each memory tag.
virtual void	SetMemoryLimit (idx_t limit=(idx_t) -1)
virtual void	SetSwapLimit (optional_idx limit=optional_idx())
	Set a new swap limit.
virtual BlockManager &	GetTemporaryBlockManager ()=0
	Get the block manager used for in-memory data.
virtual vector< TemporaryFileInformation >	GetTemporaryFiles ()
	Get the temporary file information of each temporary file.
virtual const string &	GetTemporaryDirectory () const
	Get the path to the temporary file directory.
virtual void	SetTemporaryDirectory (const string &new_dir)
	Set the path to the temporary file directory.
virtual bool	HasTemporaryDirectory () const
	Returns true, if the path to the temporary file directory is not empty.
virtual bool	HasFilesInTemporaryDirectory () const
	Returns true if there are files found in the temporary directory.
virtual unique_ptr< FileBuffer >	ConstructManagedBuffer (idx_t size, idx_t block_header_size, unique_ptr< FileBuffer > &&source, FileBufferType type=FileBufferType::MANAGED_BUFFER)
	Construct a managed buffer.
virtual BufferPool &	GetBufferPool () const
	Get the buffer pool.
virtual const DatabaseInstance &	GetDatabase () const =0
	Get the const database.
virtual DatabaseInstance &	GetDatabase ()=0
	Get the database.
virtual TemporaryMemoryManager &	GetTemporaryMemoryManager ()
	Get the manager assigning reservations for temporary memory, e.g., for query intermediates.
virtual void	PurgeQueue (const BlockHandle &handle)=0
	Purge the eviction queue of the block handle.
virtual void	AddToEvictionQueue (shared_ptr< BlockHandle > &handle)
	Add the block handle to the eviction queue.
virtual void	WriteTemporaryBuffer (MemoryTag tag, block_id_t block_id, FileBuffer &buffer)
	Write a temporary file buffer.
virtual unique_ptr< FileBuffer >	ReadTemporaryBuffer (QueryContext context, MemoryTag tag, BlockHandle &block, unique_ptr< FileBuffer > buffer)
	Read a temporary buffer.
virtual void	DeleteTemporaryFile (BlockMemory &memory)
	Delete the temporary file containing the block memory.

Static Public Member Functions
static DUCKDB_API BufferManager &	GetBufferManager (DatabaseInstance &db)
static DUCKDB_API const BufferManager &	GetBufferManager (const DatabaseInstance &db)
static DUCKDB_API BufferManager &	GetBufferManager (ClientContext &context)
static DUCKDB_API const BufferManager &	GetBufferManager (const ClientContext &context)
static DUCKDB_API BufferManager &	GetBufferManager (AttachedDatabase &db)
static DUCKDB_API idx_t	GetAllocSize (const idx_t alloc_size)

Friends
class	BufferHandle
class	BlockHandle
class	BlockManager

Constructor & Destructor Documentation

BufferManager()

duckdb::BufferManager::BufferManager ( )

inline

                    {
    }

~BufferManager()

virtual duckdb::BufferManager::~BufferManager ( )

inlinevirtual

                             {
    }

Member Function Documentation

AllocateMemory()

virtual shared_ptr< BlockHandle > duckdb::BufferManager::AllocateMemory ( MemoryTag  tag, BlockManager *  block_manager, bool  can_destroy = true  )

pure virtual

Allocate block-based memory. The block manager provides the block size, and the block header size. Returns the BlockHandle managing the registered memory.

Prefetch()

virtual void duckdb::BufferManager::Prefetch ( vector< shared_ptr< BlockHandle > > &  handles )

pure virtual

Pre-fetch a series of blocks. Using this function is a performance suggestion.

SetMemoryLimit()

virtual void duckdb::BufferManager::SetMemoryLimit ( idx_t  limit = (idx_t) -1 )

virtual

Set a new memory limit. Throws an exception, if the new limit is too low, meaning not enough blocks can be evicted.

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The documentation for this class was generated from the following file:

• external/duckdb/duckdb.hpp