temptable Namespace Reference

Classes
struct	Allocation_scheme
class	Allocator
	Custom memory allocator. More...
class	AllocatorState
	Shared state between all instances of a given allocator. More...
class	Block
	Memory-block abstraction whose purpose is to serve as a building block for custom memory-allocator implementations. More...
class	Cell
	A cell is the intersection of a row and a column. More...
class	Cell_calculator
	Utility to perform calculations for a cell. More...
class	Chunk
	Chunk is an abstraction with the purpose of representing a smallest logical memory-unit within the Block. More...
class	Column
	A column class that describes the metadata of a column. More...
class	Cursor
	A cursor for iterating over an Index. More...
struct	Exponential_policy
class	Handler
	Temptable engine handler. More...
class	Hash_duplicates
class	Hash_unique
class	Header
	Header is an abstraction with the purpose of holding and maintaining the Block metadata. More...
class	Index
	Index interface. More...
class	Indexed_cells
	Indexed cells represent one or more cells that are covered by an index. More...
class	Indexed_cells_equal_to
	Indexed cells comparator (a == b). More...
class	Indexed_cells_hash
	Indexed cells hasher. More...
class	Indexed_cells_less
	Indexed cells comparator (a < b). More...
class	Indexed_column
class	Key_value_store
	Key-value store, a convenience wrapper class which models a thread-safe dictionary type. More...
class	Key_value_store_logger
	Default Key_value_store logging facility which turns to no-op in non-debug builds. More...
class	Key_value_store_logger< T, true >
	Key_value_store logging facility debug builds only. More...
struct	Key_value_store_stats
	This is a small convenience POD-like type which describes what kind of details we are interested in when monitoring the behavior of Key_value_store. More...
struct	Largest_lock_free_type_selector
	Largest lock-free type selector, a helper utility very much similar to Lock_free_type_selector with the difference being that it tries hard not to fail. More...
struct	Largest_lock_free_type_selector< T, typename std::enable_if< std::is_integral< T >::value >::type >
	Template-specialization for integral types. More...
struct	Largest_lock_free_type_selector< T, typename std::enable_if< std::is_pointer< T >::value >::type >
	Template-specialization for pointer types. More...
class	Lock_free_pool
	Lock-free pool which consists of POOL_SIZE Lock_free_type elements. More...
class	Lock_free_shared_block_pool
	Lock-free pool of POOL_SIZE Block elements. More...
struct	Lock_free_type
	Representation of an atomic type which is guaranteed to be always-lock-free. More...
struct	Lock_free_type< T, Alignment::L1_DCACHE_SIZE, TypeSelector >
struct	Lock_free_type_selector
	Lock-free type selector, a helper utility which evaluates during the compile-time whether the given type T has a property of being always-lock-free for given platform. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_class< T >::value and std::is_trivially_copyable< T >::value >::type >
	Template-specialization for trivially-copyable classes/structs. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_pointer< T >::value >::type >
	Template-specialization for pointer types. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_same< T, bool >::value >::type >
	Template-specialization for boolean types. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_same< T, char >::value or std::is_same< T, unsigned char >::value >::type >
	Template-specialization for char types. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_same< T, int >::value or std::is_same< T, unsigned int >::value >::type >
	Template-specialization for int types. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_same< T, long >::value or std::is_same< T, unsigned long >::value >::type >
	Template-specialization for long types. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_same< T, long long >::value or std::is_same< T, unsigned long long >::value >::type >
	Template-specialization for long long types. More...
struct	Lock_free_type_selector< T, typename std::enable_if< std::is_same< T, short >::value or std::is_same< T, unsigned short >::value >::type >
	Template-specialization for short types. More...
struct	Memory
	Primary-template (functor) class for memory-utils. More...
struct	Memory< Source::MMAP_FILE >
	Template specialization for MMAP-based allocation/deallocation. More...
struct	Memory< Source::RAM >
	Template specialization for RAM-based allocation/deallocation. More...
struct	MemoryMonitor
struct	Prefer_RAM_over_MMAP_policy
class	Row
	A row representation. More...
class	Sharded_key_value_store
	Sharded key-value store, a convenience wrapper class around Key_value_store that creates N_SHARDS instances of Key_value_store and exposes a simple interface to further manipulate with them. More...
struct	Sharded_key_value_store_logger
	Default Sharded_key_value_store logging facility which turns to no-op in non-debug builds. More...
struct	Sharded_key_value_store_logger< T, true >
	Sharded_key_value_store logging facility debug builds only. More...
class	Storage
	Storage container. More...
class	Table
class	TableResourceMonitor
class	Tree

Typedefs
using	Exponential_growth_preferring_RAM_over_MMAP = Allocation_scheme< Exponential_policy, Prefer_RAM_over_MMAP_policy >
typedef std::vector< Column, Allocator< Column > >	Columns
	A type that designates all the columns of a table. More...
typedef std::multiset< Indexed_cells, Indexed_cells_less, Allocator< Indexed_cells > >	Tree_container
	The container used by tree unique and non-unique indexes. More...
typedef std::unordered_multiset< Indexed_cells, Indexed_cells_hash, Indexed_cells_equal_to, Allocator< Indexed_cells > >	Hash_duplicates_container
	The container used by hash non-unique indexes. More...
typedef std::unordered_set< Indexed_cells, Indexed_cells_hash, Indexed_cells_equal_to, Allocator< Indexed_cells > >	Hash_unique_container
	The container used by hash unique indexes. More...

Enumerations
enum class	Alignment { NATURAL , L1_DCACHE_SIZE }
	Enum class describing alignment-requirements. More...
enum class	Source { MMAP_FILE , RAM }
	Type of memory allocated. More...
enum class	Result {   END_OF_FILE = HA_ERR_END_OF_FILE , FOUND_DUPP_KEY = HA_ERR_FOUND_DUPP_KEY , KEY_NOT_FOUND = HA_ERR_KEY_NOT_FOUND , NO_SUCH_TABLE = HA_ERR_NO_SUCH_TABLE ,   OK = 0 , OUT_OF_MEM = HA_ERR_OUT_OF_MEM , RECORD_FILE_FULL = HA_ERR_RECORD_FILE_FULL , TABLE_CORRUPT = HA_ERR_TABLE_CORRUPT ,   TABLE_EXIST = HA_ERR_TABLE_EXIST , TOO_BIG_ROW = HA_ERR_TOO_BIG_ROW , UNSUPPORTED = HA_ERR_UNSUPPORTED , WRONG_COMMAND = HA_ERR_WRONG_COMMAND ,   WRONG_INDEX = HA_ERR_WRONG_INDEX }

Functions
void	Block_PSI_init ()
	Initialize the PSI memory engine. More...
void	Block_PSI_track_logical_allocation (size_t size)
	Log logical (Chunk) memory allocation. More...
void	Block_PSI_track_logical_deallocation (size_t size)
	Log logical (Chunk) memory deallocation. More...
void	Block_PSI_track_physical_ram_allocation (void *ptr, size_t size)
	Log physical memory allocation of a Block located in RAM. More...
void	Block_PSI_track_physical_ram_deallocation (uint8_t *ptr)
	Log physical memory deallocation of a Block located in RAM. More...
void	Block_PSI_track_physical_disk_allocation (void *ptr, size_t size)
	Log physical memory allocation of a Block located in MMAP-ed file. More...
void	Block_PSI_track_physical_disk_deallocation (uint8_t *ptr)
	Log physical memory deallocation of a Block located in MMAP-ed file. More...
static uint8_t *	allocate_from (Source src, size_t size)
static void	deallocate_from (Source src, size_t size, uint8_t *block_address)
constexpr unsigned long long	operator""_KiB (unsigned long long n)
	Multiply a number by 1024. More...
constexpr unsigned long long	operator""_MiB (unsigned long long n)
	Multiply a number by 1024 * 1024. More...
constexpr unsigned long long	operator""_GiB (unsigned long long n)
	Multiply a number by 1024 * 1024 * 1024. More...
void	close_connection (THD *thd)
	Helper function that performs the temptable related cleanup. More...
bool	buf_is_inside_another (const unsigned char *small, size_t small_length, const unsigned char *big, size_t big_length)
	Check if a given buffer is inside another buffer. More...
const char *	result_to_string (Result r)
static void	kv_store_shards_debug_dump ()
	Small helper function which debug-prints the miscellaneous statistics which key-value store has collected. More...
static void	log_event (const std::string &msg, loglevel lvl)
	Helper function that calls the logging API to log errors. More...
static void	erase_owned_temptables (THD *thd)
	Function that erases leaked temptables by accessing the appropriate shard for the THD involved and iterating through the shard to find all temptables owned by this THD. More...
static void	shared_block_pool_release (THD *thd)
	Small helper function which releases the slot (and memory occupied by the Block) in shared-block pool. More...
static int	show_count_hit_max_ram_var (THD *, SHOW_VAR *var, char *buff)
static void	get_count_hit_max_ram (void *, measurement_delivery_callback_t delivery, void *delivery_context)

Variables
std::atomic_uint64_t	count_hit_max_ram {}
	Status variable that counts the memory limit breaches. More...
constexpr size_t	ALLOCATOR_MAX_BLOCK_MB_EXP = 9
	log2(allocator max block size in MiB). More...
constexpr size_t	ALLOCATOR_MAX_BLOCK_BYTES
	Limit on the size of a block created by Allocator (in bytes). More...
constexpr size_t	STORAGE_PAGE_SIZE = 64_KiB
	Storage page size. More...
constexpr size_t	INDEX_DEFAULT_HASH_TABLE_BUCKETS = 1024
	Number of buckets to have by default in a hash index. More...
constexpr bool	DEBUG_BUILD = true
	Store build-type information into the constexpr expression. More...
constexpr size_t	L1_DCACHE_SIZE = CPU_LEVEL1_DCACHE_LINESIZE
	Store L1-dcache size information into the constexpr expression. More...
constexpr size_t	KV_STORE_SHARDS_COUNT = 16 * 1024
	Number of shards in key-value store. More...
constexpr size_t	SHARED_BLOCK_POOL_SIZE = 16 * 1024
	Size of a pool containing shared-blocks. More...
PSI_memory_key	mem_key_physical_disk
	PFS key to account physical allocations and deallocations from disk. More...
PSI_memory_key	mem_key_physical_ram
	PFS key to account physical allocations and deallocations from RAM. More...
PSI_memory_info	pfs_info []
	Array of PFS keys. More...
const size_t	pfs_info_num_elements = sizeof(pfs_info) / sizeof(pfs_info[0])
	Number of elements inside pfs_info[]. More...
static Sharded_key_value_store< KV_STORE_SHARDS_COUNT >	kv_store_shard
	Key-value store containing all tables for all existing connections. More...
static Lock_free_shared_block_pool< SHARED_BLOCK_POOL_SIZE >	shared_block_pool
static PSI_metric_info_v1	metrics []
static PSI_meter_info_v1	meter []
static SHOW_VAR	status_variables []

Typedef Documentation

Columns

typedef std::vector<Column, Allocator<Column> > temptable::Columns

A type that designates all the columns of a table.

Exponential_growth_preferring_RAM_over_MMAP

using temptable::Exponential_growth_preferring_RAM_over_MMAP = typedef Allocation_scheme<Exponential_policy, Prefer_RAM_over_MMAP_policy>

Hash_duplicates_container

typedef std::unordered_multiset<Indexed_cells, Indexed_cells_hash, Indexed_cells_equal_to, Allocator<Indexed_cells> > temptable::Hash_duplicates_container

The container used by hash non-unique indexes.

Hash_unique_container

typedef std::unordered_set<Indexed_cells, Indexed_cells_hash, Indexed_cells_equal_to, Allocator<Indexed_cells> > temptable::Hash_unique_container

The container used by hash unique indexes.

Tree_container

typedef std::multiset<Indexed_cells, Indexed_cells_less, Allocator<Indexed_cells> > temptable::Tree_container

The container used by tree unique and non-unique indexes.

Enumeration Type Documentation

Alignment

enum class temptable::Alignment

strong

Enum class describing alignment-requirements.

Enumerator
NATURAL
L1_DCACHE_SIZE

Result

enum class temptable::Result

strong

Enumerator
END_OF_FILE
FOUND_DUPP_KEY
KEY_NOT_FOUND
NO_SUCH_TABLE
OK
OUT_OF_MEM
RECORD_FILE_FULL
TABLE_CORRUPT
TABLE_EXIST
TOO_BIG_ROW
UNSUPPORTED
WRONG_COMMAND
WRONG_INDEX

Source

enum class temptable::Source

strong

Type of memory allocated.

Enumerator
MMAP_FILE	Memory is allocated on disk, using mmap()'ed file.
RAM	Memory is allocated from RAM, using malloc() for example.

Function Documentation

allocate_from()

static uint8_t * temptable::allocate_from ( Source  src, size_t  size  )

inlinestatic

Block_PSI_init()

void temptable::Block_PSI_init

(

)

Initialize the PSI memory engine.

Block_PSI_track_logical_allocation()

void temptable::Block_PSI_track_logical_allocation

(

size_t

size

)

Log logical (Chunk) memory allocation.

[in] Number of bytes allocated

Block_PSI_track_logical_deallocation()

void temptable::Block_PSI_track_logical_deallocation

(

size_t

size

)

Log logical (Chunk) memory deallocation.

[in] Number of bytes deallocated

Block_PSI_track_physical_disk_allocation()

void temptable::Block_PSI_track_physical_disk_allocation	(	void *	ptr,
		size_t	size
	)

Log physical memory allocation of a Block located in MMAP-ed file.

[in] Pointer to user memory block [in] Number of bytes allocated

Block_PSI_track_physical_disk_deallocation()

void temptable::Block_PSI_track_physical_disk_deallocation

(

uint8_t *

ptr

)

Log physical memory deallocation of a Block located in MMAP-ed file.

[in] Pointer to PSI header

Block_PSI_track_physical_ram_allocation()

void temptable::Block_PSI_track_physical_ram_allocation	(	void *	ptr,
		size_t	size
	)

Log physical memory allocation of a Block located in RAM.

[in] Pointer to user memory block [in] Number of bytes allocated

Block_PSI_track_physical_ram_deallocation()

void temptable::Block_PSI_track_physical_ram_deallocation

(

uint8_t *

ptr

)

Log physical memory deallocation of a Block located in RAM.

[in] Pointer to PSI header

buf_is_inside_another()

bool temptable::buf_is_inside_another ( const unsigned char *  small, size_t  small_length, const unsigned char *  big, size_t  big_length  )

inline

Check if a given buffer is inside another buffer.

Returns

true if inside

Parameters

[in]	small	First buffer, that should be inside the other.
[in]	small_length	First buffer length in bytes.
[in]	big	Second buffer, that should contain the other.
[in]	big_length	Second buffer length in bytes.

close_connection()

void temptable::close_connection

(

THD *

thd

)

Helper function that performs the temptable related cleanup.

Called from plugin->close_connection.

deallocate_from()

static void temptable::deallocate_from ( Source  src, size_t  size, uint8_t *  block_address  )

inlinestatic

erase_owned_temptables()

static void temptable::erase_owned_temptables ( THD *  thd )

static

Function that erases leaked temptables by accessing the appropriate shard for the THD involved and iterating through the shard to find all temptables owned by this THD.

This should only be called during close_connection if there is a leaked temptable in the optimizer layer, so any time this is called it indicates a bug. It logs an error to the server logs.

get_count_hit_max_ram()

static void temptable::get_count_hit_max_ram ( void *  , measurement_delivery_callback_t  delivery, void *  delivery_context  )

static

kv_store_shards_debug_dump()

static void temptable::kv_store_shards_debug_dump ( )

static

Small helper function which debug-prints the miscellaneous statistics which key-value store has collected.

log_event()

static void temptable::log_event ( const std::string &  msg, loglevel  lvl  )

static

Helper function that calls the logging API to log errors.

operator""_GiB()

constexpr unsigned long long temptable::operator""_GiB ( unsigned long long  n )

constexpr

Multiply a number by 1024 * 1024 * 1024.

Returns

n * 1024 * 1024 * 1024.

Parameters

[in]

n

Number to multiply.

operator""_KiB()

constexpr unsigned long long temptable::operator""_KiB ( unsigned long long  n )

constexpr

Multiply a number by 1024.

Returns

n * 1024.

Parameters

[in]

n

Number to multiply.

operator""_MiB()

constexpr unsigned long long temptable::operator""_MiB ( unsigned long long  n )

constexpr

Multiply a number by 1024 * 1024.

Returns

n * 1024 * 1024.

Parameters

[in]

n

Number to multiply.

result_to_string()

const char * temptable::result_to_string

(

Result

r

)

shared_block_pool_release()

static void temptable::shared_block_pool_release ( THD *  thd )

static

Small helper function which releases the slot (and memory occupied by the Block) in shared-block pool.

show_count_hit_max_ram_var()

static int temptable::show_count_hit_max_ram_var ( THD *  , SHOW_VAR *  var, char *  buff  )

static

Variable Documentation

ALLOCATOR_MAX_BLOCK_BYTES

constexpr size_t temptable::ALLOCATOR_MAX_BLOCK_BYTES

constexpr

Initial value:

= 1_MiB
                                             << ALLOCATOR_MAX_BLOCK_MB_EXP

Limit on the size of a block created by Allocator (in bytes).

A larger block could still be created if a single allocation request with bigger size is received.

ALLOCATOR_MAX_BLOCK_MB_EXP

constexpr size_t temptable::ALLOCATOR_MAX_BLOCK_MB_EXP = 9

constexpr

log2(allocator max block size in MiB).

Ie. 2 ^ ALLOCATOR_MAX_BLOCK_MB_EXP * 1024^2 = ALLOCATOR_MAX_BLOCK_BYTES.

count_hit_max_ram

std::atomic_uint64_t temptable::count_hit_max_ram {}

Status variable that counts the memory limit breaches.

DEBUG_BUILD

constexpr bool temptable::DEBUG_BUILD = true

constexpr

Store build-type information into the constexpr expression.

INDEX_DEFAULT_HASH_TABLE_BUCKETS

constexpr size_t temptable::INDEX_DEFAULT_HASH_TABLE_BUCKETS = 1024

constexpr

Number of buckets to have by default in a hash index.

kv_store_shard

Sharded_key_value_store<KV_STORE_SHARDS_COUNT> temptable::kv_store_shard

static

Key-value store containing all tables for all existing connections.

See Sharded_key_value_store documentation for more details.

KV_STORE_SHARDS_COUNT

constexpr size_t temptable::KV_STORE_SHARDS_COUNT = 16 * 1024

constexpr

Number of shards in key-value store.

L1_DCACHE_SIZE

constexpr size_t temptable::L1_DCACHE_SIZE = CPU_LEVEL1_DCACHE_LINESIZE

constexpr

Store L1-dcache size information into the constexpr expression.

mem_key_physical_disk

PSI_memory_key temptable::mem_key_physical_disk

PFS key to account physical allocations and deallocations from disk.

After we have allocated more than temptable_max_ram we start taking memory from the OS disk, using mmap()'ed files.

mem_key_physical_ram

PSI_memory_key temptable::mem_key_physical_ram

PFS key to account physical allocations and deallocations from RAM.

Before we have allocated more than temptable_max_ram we take memory from the OS RAM, using e.g. malloc().

meter

PSI_meter_info_v1 temptable::meter[]

static

Initial value:

= {
    {.m_meter = "mysql.TempTable",
     .m_description = "MySql TempTable metrics",
     .m_frequency = 10,
     .m_flags = 0,
     .m_key = 0,
     .m_metrics = metrics,
     .m_metrics_size = std::size(metrics)},
}

metrics

PSI_metric_info_v1 temptable::metrics[]

static

Initial value:

= {
    {.m_metric = "count_hit_max_ram",
     .m_unit = "",
     .m_description = "The number of times internal temp tables exceeded the "
                      "memory limit of engine",
     .m_metric_type = MetricOTELType::ASYNC_COUNTER,
     .m_num_type = MetricNumType::METRIC_INTEGER,
     .m_flags = 0,
     .m_key = 0,
     .m_measurement_callback = get_count_hit_max_ram,
     .m_measurement_context = nullptr}}

pfs_info

PSI_memory_info temptable::pfs_info[]

Initial value:

= {
 
 
 
    {&mem_key_physical_disk, "physical_disk", PSI_FLAG_MEM_COLLECT, 0,
     PSI_DOCUMENT_ME},
    {&mem_key_physical_ram, "physical_ram", PSI_FLAG_MEM_COLLECT, 0,
     PSI_DOCUMENT_ME},
}

Array of PFS keys.

pfs_info_num_elements

const size_t temptable::pfs_info_num_elements = sizeof(pfs_info) / sizeof(pfs_info[0])

Number of elements inside pfs_info[].

shared_block_pool

Lock_free_shared_block_pool<SHARED_BLOCK_POOL_SIZE> temptable::shared_block_pool

static

SHARED_BLOCK_POOL_SIZE

constexpr size_t temptable::SHARED_BLOCK_POOL_SIZE = 16 * 1024

constexpr

Size of a pool containing shared-blocks.

status_variables

SHOW_VAR temptable::status_variables[]

static

Initial value:

= {
    {.name = "TempTable_count_hit_max_ram",
     .value = (char *)&show_count_hit_max_ram_var,
     .type = SHOW_FUNC,
     .scope = SHOW_SCOPE_GLOBAL},
    {.name = NullS,
     .value = NullS,
     .type = SHOW_FUNC,
     .scope = SHOW_SCOPE_GLOBAL}}

STORAGE_PAGE_SIZE

constexpr size_t temptable::STORAGE_PAGE_SIZE = 64_KiB

constexpr

Storage page size.