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最新推荐文章于 2025-05-19 17:46:31 发布

原创最新推荐文章于 2025-05-19 17:46:31 发布 · 497 阅读

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1. Memory Information Related to Query Processor

   Query_Meta        : Memory used to manage cached meta information while Altibase server is started up
   Query_DML         : Memory used to process DML(Data Manipulation Language)
                       => Internally, this spaces is used only to manage information for sorting memory temp tables.
   Query_Sequence    : Memory used to manage sequences
   Query_Replication : Memory used to process replication
   Query_PSM_Node    : Memory used to manage PSM array variables
   Query_PSM_Execute : Memory used to execute PSM
   Query_Prepare     : Memory used to prepare queries ( creating graph,plan node, and so on)
   Query_Execute     : Memory used to execute queries
   Query_Transaction : Memory used to process trigger
   Query_Binding     : Memory used to bind host variables
   Query_Conversion : Memory used for conversion while binding host variables
   Query_Common      : Memory used to manage PSM loading, file handling, and other operations for query processing
   Mathematics       : Memory used for various calculations

2. Memory Increment during select operation

   While select operation is processed (memory temp table is being created internally),
   memory allocated for Altibase gets increased.
   However, after operation is finished, the temp space will be returned to OS block by block.

The cases when memory temp table is created generally are below and
this information can be fouond from Query_Execute of V$MEMSTAT.

   (1) when group by, order by, and (limit, order by)are used
   (2) when JOIN such as hash join and sort join is used
   (3) when set phrase such as set intersect, set difference, and set union is used
   (4) when a logical table needs to have a real data while query used view table is executed
      (In this case, you can find VMTR from the plan node.)

3. Memory Information Related to Storage Manager
    Storage_Manager             : This was used at the old version for storage modules.
                                  Now, it is divided into more specific fields as below.
    Storage_Disk_Ager           : Memory used for Disk Garbage Collection
    Storage_Disk_Buffer         : Disk Buffer Memory
    Storage_Disk_Collection     : Memory used to manage Disk Record
    Storage_Disk_Datafile       : Memory used to manage Disk File
    Storage_Disk_Index          : Memory used to manage Disk Index
    Storage_Disk_Page           : Memory used to Disk Page
    Storage_Disk_Recovery       : Memory used to recover Disk

    Storage_Memory_Ager         : Memory used for Memory Garbage Collection
    Storage_Memory_Collection   : Memory used to Memory Record
    Storage_Memory_Interface    : Memory used to manage interface such as Cursor
    Storage_Memory_Locking      : Memory used to manage Locking information
    Storage_Memory_Manager      : Memory used to manage Memory Data
    Storage_Memory_Index        : Memory used to manage Memory Index.
                                  This size is not counted as a part of MEM_MAX_DB_SIZE.
    Storage_Memory_Page         : Memory used to manage Memory Page
    Storage_Memory_Recovery     : Memory used to recover Memory
    Storage_Memory_Utility      : Memory used for Storage Manager Tool
    Storage_Memory_Transaction : Memory used to manage Transaction information

    Temp_Memory                 : Memory used to rebuild disk index or for temporary hash index processing
                                Memory space used for tasks related to temporary hash index and rebuilding disk index
                               is 100% returned to OS.
    Transaction_Table           : Memory used for Transaction Table

    Transaction_OID_List        : Memory used to store OID of Garbage Collection
    Transaction_Table_Info      : Memory used to manage Transaction Table information

    Index_Memory                : Memory used by Memory Index Manager (for example, rebuilding memory index)
                                  Memory space used for tasks related to rebuilding memory index,
                               is 100% returned to OS
    LOG_Memory                  : Memory used for lgofiles