惜分飞 » 12.1.0.2 https://www.xifenfei.com 提供7*24专业数据库(Oracle,SQL Server,MySQL,PostgreSQL等)恢复和技术支持@Tel:17813235971 Thu, 29 Oct 2026 15:31:46 +0000 zh-CN hourly 1 ORACLE 12C In-Memory功能性能测试 https://www.xifenfei.com/2014/04/oracle-12c-in-memory%e5%8a%9f%e8%83%bd%e6%b5%8b%e8%af%95.html https://www.xifenfei.com/2014/04/oracle-12c-in-memory%e5%8a%9f%e8%83%bd%e6%b5%8b%e8%af%95.html#comments Fri, 25 Apr 2014 10:16:29 +0000 https://www.xifenfei.com/?p=5266 继续阅读 →]]>

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标题：ORACLE 12C In-Memory功能性能测试

作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]

启用In-Memory功能
数据库版本12.1.0.2及其以上版本,inmemory_size参数设置为合适值

SQL> SELECT * FROM V$VERSION;

BANNER                                                                               CON_ID
-------------------------------------------------------------------------------- ----------
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit                         0
PL/SQL Release 12.1.0.2.0 -                                                               0
CORE    12.1.0.2.0                                                                        0
TNS for Linux: Version 12.1.0.2.0 -                                                       0
NLSRTL Version 12.1.0.2.0 -                                                               0

SQL> SHOW PARAMETER inmemory;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
inmemory_clause_default              string
inmemory_force                       string      DEFAULT
inmemory_query                       string      ENABLE
inmemory_size                        big integer 200M

创建表
这里可以知道,创建表大小为13631488，但是未使用In-Memory功能

SQL> create table t_xifenfei_in_memory as select * from dba_objects;

Table created.

SQL> SELECT BYTES FROM USER_SEGMENTS WHERE SEGMENT_NAME='T_XIFENFEI_IN_MEMORY';

     BYTES
----------
  13631488

SQL> select TABLE_NAME,INMEMORY_PRIORITY,INMEMORY_DISTRIBUTE,INMEMORY_COMPRESSION from user_tables;

TABLE_NAME                     INMEMORY INMEMORY_DISTRI INMEMORY_COMPRESS
------------------------------ -------- --------------- -----------------
T_XIFENFEI_IN_MEMORY

SQL>  SELECT * FROM V$INMEMORY_AREA;

POOL                       ALLOC_BYTES USED_BYTES POPULATE_STATUS                CON_ID
-------------------------- ----------- ---------- -------------------------- ----------
1MB POOL                     166723584          0 DONE                                3
64KB POOL                     33554432          0 DONE                                3

未使用In-Memory功能测试

SQL> SET AUTOT TRACE
SQL> SELECT * FROM T_XIFENFEI_IN_MEMORY;

90902 rows selected.


Execution Plan
----------------------------------------------------------
Plan hash value: 3598036702

------------------------------------------------------------------------------------------
| Id  | Operation         | Name                 | Rows  | Bytes | Cost (%CPU)| Time     |
------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |                      | 90902 |     9M|   427   (1)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| T_XIFENFEI_IN_MEMORY | 90902 |     9M|   427   (1)| 00:00:01 |
------------------------------------------------------------------------------------------


Statistics
----------------------------------------------------------
          5  recursive calls
          0  db block gets
       7505  consistent gets
       1527  physical reads
          0  redo size
   12125231  bytes sent via SQL*Net to client
      67212  bytes received via SQL*Net from client
       6062  SQL*Net roundtrips to/from client
          2  sorts (memory)
          0  sorts (disk)
      90902  rows processed

这里可以看到未使用In-Memory功能,数据库查询执行计划使用TABLE ACCESS FULL，consistent gets为7505

使用In-Memory功能测试

SQL>  alter table  T_XIFENFEI_IN_MEMORY inmemory;

Table altered.

SQL> select TABLE_NAME,INMEMORY_PRIORITY,INMEMORY_DISTRIBUTE,INMEMORY_COMPRESSION from user_tables;

TABLE_NAME                     INMEMORY INMEMORY_DISTRI INMEMORY_COMPRESS
------------------------------ -------- --------------- -----------------
T_XIFENFEI_IN_MEMORY           NONE     AUTO DISTRIBUTE FOR QUERY

--因为只是把该表设置了INMEMORY,但是未查询过,所以查询V$INMEMORY_AREA中未使用相关内存
SQL> SELECT * FROM V$INMEMORY_AREA;

POOL                       ALLOC_BYTES USED_BYTES POPULATE_STATUS                CON_ID
-------------------------- ----------- ---------- -------------------------- ----------
1MB POOL                     166723584          0 DONE                                3
64KB POOL                     33554432          0 DONE                                3

--进行一次全表扫描
SQL> SELECT COUNT(*) FROM T_XIFENFEI_IN_MEMORY;

  COUNT(*)
----------
     90902

--再次查看，已经使用了分配的In-Memory中内存
SQL> SELECT * FROM V$INMEMORY_AREA;

POOL                       ALLOC_BYTES USED_BYTES POPULATE_STATUS                CON_ID
-------------------------- ----------- ---------- -------------------------- ----------
1MB POOL                     166723584    4194304 DONE                                3
64KB POOL                     33554432     131072 DONE                                3

SQL> SET AUTOT TRACE
SQL> SELECT * FROM T_XIFENFEI_IN_MEMORY;

90902 rows selected.

Execution Plan
----------------------------------------------------------
Plan hash value: 3598036702

---------------------------------------------------------------------------------------------------
| Id  | Operation                  | Name                 | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT           |                      | 90902 |     9M|    20  (45)| 00:00:01 |
|   1 |  TABLE ACCESS INMEMORY FULL| T_XIFENFEI_IN_MEMORY | 90902 |     9M|    20  (45)| 00:00:01 |
---------------------------------------------------------------------------------------------------


Statistics
----------------------------------------------------------
          3  recursive calls
          0  db block gets
          4  consistent gets
          0  physical reads
          0  redo size
    4946298  bytes sent via SQL*Net to client
      67212  bytes received via SQL*Net from client
       6062  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
      90902  rows processed

这里我们可以发现，使用了In-Memory功能之后，数据库consistent gets为4,相比未使用In-Memory之前的7505,性能最少提高近2000倍.

]]> https://www.xifenfei.com/2014/04/oracle-12c-in-memory%e5%8a%9f%e8%83%bd%e6%b5%8b%e8%af%95.html/feed 0 ORACLE 12C In-Memory组件初试 https://www.xifenfei.com/2014/04/oracle-12c-in-memory%e7%bb%84%e4%bb%b6%e5%88%9d%e8%af%95.html https://www.xifenfei.com/2014/04/oracle-12c-in-memory%e7%bb%84%e4%bb%b6%e5%88%9d%e8%af%95.html#comments Thu, 24 Apr 2014 15:10:42 +0000 https://www.xifenfei.com/?p=5259 继续阅读 →]]>

联系：手机/微信(+86 17813235971) QQ(107644445)QQ咨询惜分飞

标题：ORACLE 12C In-Memory组件初试

作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]

根据Oracle官方的宣传12.1.0.2的In-Memory组件实现内存列存储提高Oracle性能而且弥补在列存储中的不足。感谢Lunar的文档支持
12.1.0.2版本

[oracle@localhost ~]$ sqlplus chf/xifenfei@pdb1

SQL*Plus: Release 12.1.0.2.0 Beta on Thu Apr 24 21:39:43 2014

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit     
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

SQL> select * from v$version;

BANNER                                                                               CON_ID
-------------------------------------------------------------------------------- ----------
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit                         0
PL/SQL Release 12.1.0.2.0 -                                                               0
CORE    12.1.0.2.0                                                                        0
TNS for Linux: Version 12.1.0.2.0 -                                                       0
NLSRTL Version 12.1.0.2.0 -                                                               0

关于In-Memory组件

SQL>  select parameter,value from v$option where parameter like 'In-Memory%';

PARAMETER                                                        VALUE
---------------------------------------------------------------- -------------
In-Memory Column Store                                           TRUE
In-Memory Aggregation                                            TRUE

关于inmemory参数

SQL> select NAME,value,DESCRIPTION from v$parameter where NAME like 'inmemory%';

NAME                 VALUE
-------------------- --------------------
DESCRIPTION
---------------------------------------------------
inmemory_size        0
size in bytes of in-memory area

inmemory_clause_defa
ult
Default in-memory clause for new tables

inmemory_force       DEFAULT
Force tables to be in-memory or not

inmemory_query       ENABLE
Specifies whether in-memory queries are allowed

启用In-Memory功能

SQL> show parameter inmemory;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
inmemory_clause_default              string
inmemory_force                       string      DEFAULT
inmemory_query                       string      ENABLE
inmemory_size                        big integer 0

SQL> alter system set inmemory_size=200M scope=spfile;

System altered.

SQL> shutdown immediate
Pluggable Database closed.
SQL> startup
Pluggable Database opened.
SQL> show parameter inmemory;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ----------------------
inmemory_clause_default              string
inmemory_force                       string      DEFAULT
inmemory_query                       string      ENABLE
inmemory_size                        big integer 200M

创建测试表

SQL> create table t_xifenfei_in_memory as select * from dba_objects;

Table created.

SQL> select TABLE_NAME,INMEMORY_PRIORITY,INMEMORY_DISTRIBUTE,INMEMORY_COMPRESSION from user_tables;

TABLE_NAME                     INMEMORY INMEMORY_DISTRI INMEMORY_COMPRESS
------------------------------ -------- --------------- -----------------
T_XIFENFEI_IN_MEMORY

SQL> alter table  T_XIFENFEI_IN_MEMORY inmemory;

Table altered.

SQL> select TABLE_NAME,INMEMORY_PRIORITY,INMEMORY_DISTRIBUTE,INMEMORY_COMPRESSION from user_tables;

TABLE_NAME                INMEMORY INMEMORY_DISTRI INMEMORY_COMPRESS
------------------------- -------- --------------- -----------------
T_XIFENFEI_IN_MEMORY      NONE     AUTO DISTRIBUTE FOR QUERY
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