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22.5.10.27 The ndbinfo memory_per_fragment Table
The memory_per_fragment
table provides
information about the usage of memory by individual fragments.
The following table provides information about the columns in
the memory_per_fragment
table. For each
column, the table shows the name, data type, and a brief
description. Additional information can be found in the notes
following the table.
Table 22.401 Columns of the memory_per_fragment table
Column Name | Type | Description |
---|---|---|
fq_name | string | Name of this fragment |
parent_fq_name | string | Name of this fragment's parent |
type | string | Type of object; see text for possible values |
table_id | integer | Table ID for this table |
node_id | integer | Node ID for this node |
block_instance | integer | Kernel block instance ID |
fragment_num | integer | Fragment ID (number) |
fixed_elem_alloc_bytes | integer | Number of bytes allocated for fixed-sized elements |
fixed_elem_free_bytes | integer | Free bytes remaining in pages allocated to fixed-size elements |
fixed_elem_size_bytes | integer | Length of each fixed-size element in bytes |
fixed_elem_count | integer | Number of fixed-size elements |
fixed_elem_free_count | decimal | Number of free rows for fixed-size elements |
var_elem_alloc_bytes | integer | Number of bytes allocated for variable-size elements |
var_elem_free_bytes | integer | Free bytes remaining in pages allocated to variable-size elements |
var_elem_count | integer | Number of variable-size elements |
hash_index_alloc_bytes | integer | Number of bytes allocated to hash indexes |
The type
column from this table shows the
dictionary object type used for this fragment
(Object::Type
, in the NDB API),
and can take any one of the values shown in the following list:
System table
User table
Unique hash index
Hash index
Unique ordered index
Ordered index
Hash index trigger
Subscription trigger
Read only constraint
Index trigger
Reorganize trigger
Tablespace
Log file group
Data file
Undo file
Hash map
Foreign key definition
Foreign key parent trigger
Foreign key child trigger
Schema transaction
You can also obtain this list by executing
SELECT * FROM
ndbinfo.dict_obj_types
in the
mysql client.
The block_instance
column provides the NDB
kernel block instance number. You can use this to obtain
information about specific threads from the
threadblocks
table.
Document created the 26/06/2006, last modified the 26/10/2018
Source of the printed document:https://www.gaudry.be/en/mysql-rf-mysql-cluster-ndbinfo-memory-per-fragment.html
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