duckdb::BlockMemory Class Reference

Inheritance diagram for duckdb::BlockMemory:

Collaboration diagram for duckdb::BlockMemory:

Public Member Functions
	BlockMemory (BufferManager &buffer_manager, block_id_t block_id_p, MemoryTag tag_p, idx_t block_alloc_size)
	BlockMemory (BufferManager &buffer_manager, block_id_t block_id_p, MemoryTag tag_p, unique_ptr< FileBuffer > buffer_p, DestroyBufferUpon destroy_buffer_upon_p, idx_t size_p, BufferPoolReservation &&reservation)
const BufferManager &	GetBufferManager () const
	Returns a const reference to the buffer manager.
BufferManager &	GetBufferManager ()
	Returns a reference to the buffer manager.
block_id_t	BlockId () const
	Returns the block ID.
BlockLock	GetLock ()
	Locks the memory block.
void	VerifyMutex (BlockLock &l) const
	Verification-only: ensure that the lock matches this memory's lock.
BlockState	GetState () const
	Returns the block state.
void	SetState (BlockState state_p)
	Sets the block state.
bool	IsUnloaded () const
	Returns true, if the block state is BLOCK_UNLOADED.
int32_t	GetReaders () const
	Returns the number of readers.
int32_t	IncrementReaders ()
	Increments the number of readers prior to returning it.
int32_t	DecrementReaders ()
	Decrements the number of readers prior to returning it.
void	SetReaders (int32_t n)
	Sets the number of readers.
MemoryTag	GetMemoryTag () const
	Returns the memory tag.
FileBufferType	GetBufferType () const
	Returns the file buffer type.
unique_ptr< FileBuffer > &	GetBuffer (BlockLock &l)
	Returns a reference to the unique file buffer pointer while holding the block lock.
unique_ptr< FileBuffer > &	GetBuffer ()
	Returns a reference to the unique file buffer pointer.
void	SetBuffer (unique_ptr< FileBuffer > buffer_p)
	Sets the file buffer.
idx_t	GetEvictionSequenceNumber () const
	Returns the eviction sequence number.
idx_t	NextEvictionSequenceNumber ()
	Increments the eviction sequence number prior to returning it.
int64_t	GetLRUTimestamp () const
	Get the LRU timestamp.
void	SetLRUTimestamp (int64_t timestamp_msec)
	Set the LRU timestamp.
void	SetDestroyBufferUpon (DestroyBufferUpon destroy_buffer_upon_p)
	Set the buffer destruction policy.
bool	MustAddToEvictionQueue () const
	Returns true, if the buffer must be added to the eviction queue.
bool	MustWriteToTemporaryFile () const
	Returns true, if the buffer cannot be destroyed, but must be kept alive in a temporary file.
idx_t	GetMemoryUsage () const
	Returns the memory usage.
void	SetMemoryUsage (idx_t usage)
	Sets the memory usage.
BufferPoolReservation &	GetMemoryCharge (BlockLock &l)
	Get the memory charge while holding the block lock.
BufferPoolReservation &	GetMemoryCharge ()
	Get the memory charge.
void	ResizeMemory (BlockLock &l, idx_t alloc_size)
	Resize the memory charge.
void	MergeMemoryReservation (BlockLock &l, BufferPoolReservation reservation)
	Merge two memory charges.
bool	IsSwizzled () const
	Returns true, if there is a swizzled memory pointer, else false.
void	SetSwizzling (const char *unswizzler)
	Sets the swizzled memory pointer.
void	SetEvictionQueueIndex (const idx_t index)
	Sets the eviction queue index.
idx_t	GetEvictionQueueIndex () const
	Returns the eviction queue index.
void	ChangeMemoryUsage (BlockLock &l, int64_t delta)
void	ConvertToPersistent (BlockLock &l, BlockHandle &new_block, unique_ptr< FileBuffer > new_buffer)
void	ResizeBuffer (BlockLock &l, idx_t block_size, idx_t block_header_size, int64_t memory_delta)
bool	CanUnload () const
unique_ptr< FileBuffer >	UnloadAndTakeBlock (BlockLock &l)
void	Unload (BlockLock &l)
Public Member Functions inherited from duckdb::enable_shared_from_this< BlockMemory >
shared_ptr< BlockMemory >	shared_from_this ()
shared_ptr< BlockMemory const >	shared_from_this () const

Private Attributes
BufferManager &	buffer_manager
	A reference to the buffer manager.
const block_id_t	block_id
	The block id of the block.
mutex	lock
	The block-level lock.
atomic< BlockState >	state
	Whether the block is loaded or unloaded.
atomic< int32_t >	readers
	The number of concurrent readers.
const MemoryTag	tag
	The memory tag.
const FileBufferType	buffer_type
	The file buffer type.
unique_ptr< FileBuffer >	buffer
	A pointer to the loaded data, if any.
atomic< idx_t >	eviction_seq_num
	The internal eviction sequence number.
atomic< int64_t >	lru_timestamp_msec
	The LRU timestamp for age-based eviction.
atomic< DestroyBufferUpon >	destroy_buffer_upon
	When to destroy the data buffer.
atomic< idx_t >	memory_usage
BufferPoolReservation	memory_charge
	The current memory reservation/usage.
const char *	unswizzled
	Swizzled memory pointers.
atomic< idx_t >	eviction_queue_idx
	The eviction queue index, currently only FileBufferType::MANAGED_BUFFER.

Additional Inherited Members
Protected Member Functions inherited from duckdb::enable_shared_from_this< BlockMemory >
	enable_shared_from_this (enable_shared_from_this const &) noexcept
enable_shared_from_this &	operator= (enable_shared_from_this const &) noexcept

Member Function Documentation

GetBufferManager() [1/2]

const BufferManager & duckdb::BlockMemory::GetBufferManager ( ) const

inline

Returns a const reference to the buffer manager.

                                                  {
        return buffer_manager;
    }

GetBufferManager() [2/2]

BufferManager & duckdb::BlockMemory::GetBufferManager ( )

inline

Returns a reference to the buffer manager.

                                      {
        return buffer_manager;
    }

BlockId()

block_id_t duckdb::BlockMemory::BlockId ( ) const

inline

Returns the block ID.

                               {
        return block_id;
    }

GetLock()

BlockLock duckdb::BlockMemory::GetLock ( )

inline

Locks the memory block.

                        {
        return BlockLock(lock);
    }

VerifyMutex()

void duckdb::BlockMemory::VerifyMutex ( BlockLock &  l ) const

inline

Verification-only: ensure that the lock matches this memory's lock.

                                         {
        D_ASSERT(l.owns_lock());
        D_ASSERT(l.mutex() == &lock);
    }

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GetState()

BlockState duckdb::BlockMemory::GetState ( ) const

inline

Returns the block state.

                                {
        return state;
    }

SetState()

void duckdb::BlockMemory::SetState ( BlockState  state_p )

inline

Sets the block state.

                                      {
        state = state_p;
    }

IsUnloaded()

bool duckdb::BlockMemory::IsUnloaded ( ) const

inline

Returns true, if the block state is BLOCK_UNLOADED.

                            {
        return state == BlockState::BLOCK_UNLOADED;
    }

GetReaders()

int32_t duckdb::BlockMemory::GetReaders ( ) const

inline

Returns the number of readers.

                               {
        return readers;
    }

IncrementReaders()

int32_t duckdb::BlockMemory::IncrementReaders ( )

inline

Increments the number of readers prior to returning it.

                               {
        return ++readers;
    }

DecrementReaders()

int32_t duckdb::BlockMemory::DecrementReaders ( )

inline

Decrements the number of readers prior to returning it.

                               {
        return --readers;
    }

SetReaders()

void duckdb::BlockMemory::SetReaders ( int32_t  n )

inline

Sets the number of readers.

                               {
        readers = n;
    }

GetMemoryTag()

MemoryTag duckdb::BlockMemory::GetMemoryTag ( ) const

inline

Returns the memory tag.

                                   {
        return tag;
    }

GetBufferType()

FileBufferType duckdb::BlockMemory::GetBufferType ( ) const

inline

Returns the file buffer type.

                                         {
        return buffer_type;
    }

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GetBuffer() [1/2]

unique_ptr< FileBuffer > & duckdb::BlockMemory::GetBuffer ( BlockLock &  l )

inline

Returns a reference to the unique file buffer pointer while holding the block lock.

                                                    {
        VerifyMutex(l);
        return GetBuffer();
    }

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GetBuffer() [2/2]

unique_ptr< FileBuffer > & duckdb::BlockMemory::GetBuffer ( )

inline

Returns a reference to the unique file buffer pointer.

                                        {
        return buffer;
    }

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SetBuffer()

void duckdb::BlockMemory::SetBuffer ( unique_ptr< FileBuffer >  buffer_p )

inline

Sets the file buffer.

                                                    {
        buffer = std::move(buffer_p);
    }

GetEvictionSequenceNumber()

idx_t duckdb::BlockMemory::GetEvictionSequenceNumber ( ) const

inline

Returns the eviction sequence number.

                                            {
        return eviction_seq_num;
    }

NextEvictionSequenceNumber()

idx_t duckdb::BlockMemory::NextEvictionSequenceNumber ( )

inline

Increments the eviction sequence number prior to returning it.

                                       {
        return ++eviction_seq_num;
    }

GetLRUTimestamp()

int64_t duckdb::BlockMemory::GetLRUTimestamp ( ) const

inline

Get the LRU timestamp.

                                    {
        return lru_timestamp_msec;
    }

SetLRUTimestamp()

void duckdb::BlockMemory::SetLRUTimestamp ( int64_t  timestamp_msec )

inline

Set the LRU timestamp.

                                                 {
        lru_timestamp_msec = timestamp_msec;
    }

SetDestroyBufferUpon()

void duckdb::BlockMemory::SetDestroyBufferUpon ( DestroyBufferUpon  destroy_buffer_upon_p )

inline

Set the buffer destruction policy.

                                                                       {
        destroy_buffer_upon = destroy_buffer_upon_p;
    }

MustAddToEvictionQueue()

bool duckdb::BlockMemory::MustAddToEvictionQueue ( ) const

inline

Returns true, if the buffer must be added to the eviction queue.

                                        {
        return destroy_buffer_upon != DestroyBufferUpon::UNPIN;
    }

MustWriteToTemporaryFile()

bool duckdb::BlockMemory::MustWriteToTemporaryFile ( ) const

inline

Returns true, if the buffer cannot be destroyed, but must be kept alive in a temporary file.

                                          {
        return destroy_buffer_upon == DestroyBufferUpon::BLOCK;
    }

GetMemoryUsage()

idx_t duckdb::BlockMemory::GetMemoryUsage ( ) const

inline

Returns the memory usage.

                                 {
        return memory_usage;
    }

SetMemoryUsage()

void duckdb::BlockMemory::SetMemoryUsage ( idx_t  usage )

inline

Sets the memory usage.

                                     {
        memory_usage = usage;
    }

GetMemoryCharge() [1/2]

BufferPoolReservation & duckdb::BlockMemory::GetMemoryCharge ( BlockLock &  l )

inline

Get the memory charge while holding the block lock.

                                                         {
        VerifyMutex(l);
        return GetMemoryCharge();
    }

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GetMemoryCharge() [2/2]

BufferPoolReservation & duckdb::BlockMemory::GetMemoryCharge ( )

inline

Get the memory charge.

                                             {
        return memory_charge;
    }

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ResizeMemory()

void duckdb::BlockMemory::ResizeMemory ( BlockLock &  l, idx_t  alloc_size  )

inline

Resize the memory charge.

                                                      {
        VerifyMutex(l);
        memory_charge.Resize(alloc_size);
    }

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MergeMemoryReservation()

void duckdb::BlockMemory::MergeMemoryReservation ( BlockLock &  l, BufferPoolReservation  reservation  )

inline

Merge two memory charges.

                                                                                 {
        VerifyMutex(l);
        memory_charge.Merge(std::move(reservation));
    }

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IsSwizzled()

bool duckdb::BlockMemory::IsSwizzled ( ) const

inline

Returns true, if there is a swizzled memory pointer, else false.

                            {
        return !unswizzled;
    }

SetSwizzling()

void duckdb::BlockMemory::SetSwizzling ( const char *  unswizzler )

inline

Sets the swizzled memory pointer.

                                              {
        unswizzled = unswizzler;
    }

SetEvictionQueueIndex()

void duckdb::BlockMemory::SetEvictionQueueIndex ( const idx_t  index )

inline

Sets the eviction queue index.

                                                  {
        // The index can only be set once.
        D_ASSERT(eviction_queue_idx == DConstants::INVALID_INDEX);
        // It can only be set for managed buffers (for now).
        D_ASSERT(GetBufferType() == FileBufferType::MANAGED_BUFFER);
        eviction_queue_idx = index;
    }

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GetEvictionQueueIndex()

idx_t duckdb::BlockMemory::GetEvictionQueueIndex ( ) const

inline

Returns the eviction queue index.

                                        {
        return eviction_queue_idx;
    }

CanUnload()

bool duckdb::BlockMemory::CanUnload

(

)

const

Returns whether the block can be unloaded or not. The state here can change if the block lock is held. However, this method does not hold the block lock.

Member Data Documentation

memory_usage

atomic<idx_t> duckdb::BlockMemory::memory_usage

private

The memory usage of the block when loaded. Determines the memory to reserve when pinning/loading an unloaded block.

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

• external/duckdb/duckdb.hpp