foedus::storage::array::ArrayMetadata Struct Reference

Metadata of an array storage. More...

Detailed Description

Metadata of an array storage.

Definition at line 40 of file array_metadata.hpp.

#include <array_metadata.hpp>

Inheritance diagram for foedus::storage::array::ArrayMetadata:

Collaboration diagram for foedus::storage::array::ArrayMetadata:

Public Types
enum	Constants { kDefaultSnapshotDropVolatilePagesThreshold = 3 }

Public Member Functions
	ArrayMetadata ()
	ArrayMetadata (StorageId id, const StorageName &name, uint16_t payload_size, ArrayOffset array_size)
	ArrayMetadata (const StorageName &name, uint16_t payload_size, ArrayOffset array_size)
	This one is for newly creating a storage. More...
std::string	describe () const
Public Member Functions inherited from foedus::storage::Metadata
	Metadata ()
	Metadata (StorageId id, StorageType type, const StorageName &name)
	Metadata (StorageId id, StorageType type, const StorageName &name, SnapshotPagePointer root_snapshot_page_id)
bool	keeps_all_volatile_pages () const

Public Attributes
uint16_t	payload_size_
	byte size of one record in this array storage without internal overheads More...
uint16_t	snapshot_drop_volatile_pages_threshold_
	Number of levels of volatile pages to keep after each snapshotting. More...
uint32_t	padding_
ArrayOffset	array_size_
	Size of this array. More...
Public Attributes inherited from foedus::storage::Metadata
StorageId	id_
	the unique ID of this storage. More...
StorageType	type_
	type of the storage. More...
StorageName	name_
	the unique name of this storage. More...
SnapshotPagePointer	root_snapshot_page_id_
	Pointer to a snapshotted page this storage is rooted at. More...
SnapshotThresholds	snapshot_thresholds_

Friends
std::ostream &	operator<< (std::ostream &o, const ArrayMetadata &v)

Additional Inherited Members
Static Public Member Functions inherited from foedus::storage::Metadata
static std::string	describe (const Metadata &metadata)
	to_string operator of all Metadata objects. More...

Member Enumeration Documentation

enum foedus::storage::array::ArrayMetadata::Constants

Enumerator
kDefaultSnapshotDropVolatilePagesThreshold

Definition at line 41 of file array_metadata.hpp.

                 {
    kDefaultSnapshotDropVolatilePagesThreshold = 3,
  };

Constructor & Destructor Documentation

foedus::storage::array::ArrayMetadata::ArrayMetadata ( )

inline

Definition at line 44 of file array_metadata.hpp.

    : Metadata(0, kArrayStorage, ""),
    payload_size_(0),
    snapshot_drop_volatile_pages_threshold_(kDefaultSnapshotDropVolatilePagesThreshold),
    padding_(0),
    array_size_(0) {}

foedus::storage::array::ArrayMetadata::ArrayMetadata ( StorageId  id, const StorageName &  name, uint16_t  payload_size, ArrayOffset  array_size  )

inline

Definition at line 50 of file array_metadata.hpp.

    : Metadata(id, kArrayStorage, name),
    payload_size_(payload_size),
    snapshot_drop_volatile_pages_threshold_(kDefaultSnapshotDropVolatilePagesThreshold),
    padding_(0),
    array_size_(array_size) {
  }

foedus::storage::array::ArrayMetadata::ArrayMetadata ( const StorageName &  name, uint16_t  payload_size, ArrayOffset  array_size  )

inline

This one is for newly creating a storage.

Definition at line 62 of file array_metadata.hpp.

    : Metadata(0, kArrayStorage, name),
    payload_size_(payload_size),
    snapshot_drop_volatile_pages_threshold_(kDefaultSnapshotDropVolatilePagesThreshold),
    padding_(0),
    array_size_(array_size) {
  }

Member Function Documentation

std::string foedus::storage::array::ArrayMetadata::describe

(

)

const

Definition at line 28 of file array_metadata.cpp.

                                        {
  std::stringstream o;
  o << ArrayMetadataSerializer(const_cast<ArrayMetadata*>(this));
  return o.str();
}

Friends And Related Function Documentation

std::ostream& operator<< ( std::ostream &  o, const ArrayMetadata &  v  )

friend

Definition at line 33 of file array_metadata.cpp.

                                                              {
  o << ArrayMetadataSerializer(const_cast<ArrayMetadata*>(&v));
  return o;
}

Member Data Documentation

ArrayOffset foedus::storage::array::ArrayMetadata::array_size_

Size of this array.

Definition at line 85 of file array_metadata.hpp.

Referenced by foedus::storage::array::calculate_levels(), foedus::storage::array::ArrayStoragePimpl::get_array_size(), foedus::storage::array::ArrayMetadataSerializer::load(), foedus::storage::array::ArrayStoragePimpl::load_empty(), and foedus::storage::array::ArrayMetadataSerializer::save().

uint32_t foedus::storage::array::ArrayMetadata::padding_

Definition at line 83 of file array_metadata.hpp.

uint16_t foedus::storage::array::ArrayMetadata::payload_size_

byte size of one record in this array storage without internal overheads

Definition at line 74 of file array_metadata.hpp.

Referenced by foedus::storage::array::calculate_levels(), foedus::storage::array::ArrayStoragePimpl::get_payload_size(), foedus::storage::array::ArrayMetadataSerializer::load(), foedus::storage::array::ArrayStoragePimpl::load_empty(), and foedus::storage::array::ArrayMetadataSerializer::save().

uint16_t foedus::storage::array::ArrayMetadata::snapshot_drop_volatile_pages_threshold_

Number of levels of volatile pages to keep after each snapshotting.

0 means this storage keeps no volatile pages after snapshotting. 1 means it keeps only the root page, 2 means another level, ... The default is 3. Keeping 256^2=64k pages in higher level should hit a good balance. If it doesn't, the user (you) chooses the right value per storage.

Definition at line 82 of file array_metadata.hpp.

Referenced by foedus::storage::array::ArrayStoragePimpl::get_snapshot_drop_volatile_pages_threshold(), foedus::storage::array::ArrayMetadataSerializer::load(), and foedus::storage::array::ArrayMetadataSerializer::save().

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The documentation for this struct was generated from the following files:

• /home/shino/foedus_code/foedus-core/include/foedus/storage/array/array_metadata.hpp
• /home/shino/foedus_code/foedus-core/src/foedus/storage/array/array_metadata.cpp