about Undo Tablespace used High ?

最新推荐文章于 2025-07-06 18:23:34 发布
转载 最新推荐文章于 2025-07-06 18:23:34 发布 · 133 阅读 · 0 ·
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原文链接：http://www.cnblogs.com/lovewifelovelife/archive/2012/12/07/3295003.html

本文详细探讨了Undo表空间使用率高的原因及其对数据库性能的影响，提供了深入的分析和有效的解决策略。
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2025-10-24T06:14:45.483589Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2025-10-24T06:14:45.487190Z 0 [Note] C:\Program Files\MySQL\MySQL Server 5.7\bin\mysqld.exe (mysqld 5.7.43-log) starting as process 2792 ... 2025-10-24T06:14:45.499521Z 0 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions 2025-10-24T06:14:45.500924Z 0 [Note] InnoDB: Uses event mutexes 2025-10-24T06:14:45.501775Z 0 [Note] InnoDB: _mm_lfence() and _mm_sfence() are used for memory barrier 2025-10-24T06:14:45.503093Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.13 2025-10-24T06:14:45.509869Z 0 [Note] InnoDB: Number of pools: 1 2025-10-24T06:14:45.510876Z 0 [Note] InnoDB: Not using CPU crc32 instructions 2025-10-24T06:14:45.516358Z 0 [Note] InnoDB: Initializing buffer pool, total size = 4G, instances = 8, chunk size = 128M 2025-10-24T06:14:45.739511Z 0 [Note] InnoDB: Completed initialization of buffer pool 2025-10-24T06:14:45.866688Z 0 [Note] InnoDB: Highest supported file format is Barracuda. 2025-10-24T06:14:45.917325Z 0 [Note] InnoDB: Log scan progressed past the checkpoint lsn 1818072334033 2025-10-24T06:14:45.919665Z 0 [Note] InnoDB: Doing recovery: scanned up to log sequence number 1818072343203 2025-10-24T06:14:46.501026Z 0 [Note] InnoDB: Database was not shutdown normally! 2025-10-24T06:14:46.502853Z 0 [Note] InnoDB: Starting crash recovery. 2025-10-24T06:14:53.325953Z 0 [Note] InnoDB: Removed temporary tablespace data file: "ibtmp1" 2025-10-24T06:14:53.328050Z 0 [Note] InnoDB: Creating shared tablespace for temporary tables 2025-10-24T06:14:53.331419Z 0 [Note] InnoDB: Setting file '.\ibtmp1' size to 12 MB. Physically writing the file full; Please wait ... 2025-10-24T06:14:53.341449Z 0 [Note] InnoDB: File '.\ibtmp1' size is now 12 MB. 2025-10-24T06:14:53.377635Z 0 [Note] InnoDB: 96 redo rollback segment(s) found. 96 redo rollback segment(s) are active. 2025-10-24T06:14:53.379973Z 0 [Note] InnoDB: 32 non-redo rollback segment(s) are active. 2025-10-24T06:14:53.382232Z 0 [Note] InnoDB: Waiting for purge to start 2025-10-24T06:14:53.434201Z 0 [Note] InnoDB: page_cleaner: 1000ms intended loop took 7651ms. The settings might not be optimal. (flushed=0 and evicted=0, during the time.) 2025-10-24T06:14:53.434424Z 0 [Note] InnoDB: 5.7.43 started; log sequence number 1818072343203 2025-10-24T06:14:53.440369Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=3] log sequence number 1818075015616 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.440496Z 0 [Note] InnoDB: Loading buffer pool(s) from D:\MySql\data\ib_buffer_pool 2025-10-24T06:14:53.444882Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.454213Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=2] log sequence number 1818075015133 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.457121Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.459265Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=13] log sequence number 1818075023156 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.459333Z 0 [Note] Plugin 'FEDERATED' is disabled. 2025-10-24T06:14:53.461391Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=4] log sequence number 1818074852082 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.464302Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.468966Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=8883] log sequence number 1818075644951 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.469327Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.478059Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.481293Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=5] log sequence number 1818074822726 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.488992Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.493841Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=8] log sequence number 1818073611600 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.496594Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.499300Z 0 [ERROR] InnoDB: Page [page id: space=488, page number=3] log sequence number 1818075769646 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.500195Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=22] log sequence number 1818074006086 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.503793Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.505862Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.513791Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=23] log sequence number 1818074993296 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.515785Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.524243Z 0 [ERROR] InnoDB: Page [page id: space=488, page number=527] log sequence number 1818080514186 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.528019Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.537996Z 0 [ERROR] InnoDB: Page [page id: space=540, page number=7] log sequence number 1818081166468 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.541042Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.543656Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=31] log sequence number 1818075024348 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.548712Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.554624Z 0 [ERROR] InnoDB: Page [page id: space=540, page number=4] log sequence number 1818081150547 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.558427Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.565031Z 0 [ERROR] InnoDB: Page [page id: space=539, page number=4] log sequence number 1818080173025 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.567157Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=31683] log sequence number 1818075654250 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.567489Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.571042Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.598497Z 0 [Note] Found ca.pem, server-cert.pem and server-key.pem in data directory. Trying to enable SSL support using them. 2025-10-24T06:14:53.601463Z 0 [Note] Skipping generation of SSL certificates as certificate files are present in data directory. 2025-10-24T06:14:53.603981Z 0 [Warning] A deprecated TLS version TLSv1 is enabled. Please use TLSv1.2 or higher. 2025-10-24T06:14:53.605450Z 0 [ERROR] InnoDB: Page [page id: space=743, page number=0] log sequence number 1818074641633 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.606048Z 0 [Warning] A deprecated TLS version TLSv1.1 is enabled. Please use TLSv1.2 or higher. 2025-10-24T06:14:53.609638Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. InnoDB: Dump of the tablespace extent descriptor: len 40; hex 0000000000000000ffffffff0000ffffffff000000000002aaffffffffffffffffffffffffffffff; asc ;2025-10-24T06:14:53.618233Z 0 [ERROR] InnoDB: InnoDB is trying to free page [page id: space=743, page number=8] though it is already marked as free in the tablespace! The tablespace free space info is corrupt. You may need to dump your tables and recreate the whole database! 2025-10-24T06:14:53.622034Z 0 [ERROR] [FATAL] InnoDB: Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.624235Z 0 [Warning] CA certificate ca.pem is self signed. 2025-10-24 14:14:53 0x354c InnoDB: Assertion failure in thread 13644 in file ut0ut.cc line 921 InnoDB: We intentionally generate a memory trap. InnoDB: Submit a detailed bug report to http://bugs.mysql.com. InnoDB: If you get repeated assertion failures or crashes, even InnoDB: immediately after the mysqld startup, there may be InnoDB: corruption in the InnoDB tablespace. Please refer to InnoDB: http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html InnoDB: about forcing recovery. 2025-10-24T06:14:53.625645Z 0 [Note] Skipping generation of RSA key pair as key files are present in data directory. 2025-10-24T06:14:53.628676Z 0 [Note] Server hostname (bind-address): '*'; port: 3308 2025-10-24T06:14:53.629979Z 0 [Note] IPv6 is available. 2025-10-24T06:14:53.630668Z 0 [Note] - '::' resolves to '::'; 2025-10-24T06:14:53.632389Z 0 [Note] Server socket created on IP: '::'. 2025-10-24T06:14:53.747077Z 0 [ERROR] InnoDB: Page [page id: space=26, page number=16384] log sequence number 1818075741603 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:53.751073Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:53.924848Z 0 [Note] Failed to start slave threads for channel '' 2025-10-24T06:14:54.002381Z 0 [Note] Event Scheduler: Loaded 0 events 2025-10-24T06:14:54.003266Z 0 [Note] C:\Program Files\MySQL\MySQL Server 5.7\bin\mysqld.exe: ready for connections. Version: '5.7.43-log' socket: '' port: 3308 MySQL Community Server (GPL) 2025-10-24T06:14:54.063857Z 0 [ERROR] InnoDB: Page [page id: space=28, page number=0] log sequence number 1818073721575 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:54.067646Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:54.073181Z 0 [ERROR] InnoDB: Page [page id: space=28, page number=4] log sequence number 1818073721575 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:54.076879Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:54.081031Z 0 [ERROR] InnoDB: Page [page id: space=28, page number=5] log sequence number 1818073639109 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:54.083439Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:54.087366Z 0 [ERROR] InnoDB: Page [page id: space=488, page number=0] log sequence number 1818074963526 is in the future! Current system log sequence number 1818072347793. 2025-10-24T06:14:54.089008Z 0 [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery. 2025-10-24T06:14:54.840960Z 0 [Note] InnoDB: Buffer pool(s) load completed at 251024 14:14:54
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基于径向基函数神经网络RBFNN的自适应滑模控制学习（Matlab代码实现）内容概要：本文介绍了基于径向基函数神经网络（RBFNN）的自适应滑模控制方法，并提供了相应的Matlab代码实现。该方法结合了RBF神经网络的非线性逼近能力和滑模控制的强鲁棒性，用于解决复杂系统的控制问题，尤其适用于存在不确定性和外部干扰的动态系统。文中详细阐述了控制算法的设计思路、RBFNN的结构与权重更新机制、滑模面的构建以及自适应律的推导过程，并通过Matlab仿真验证了所提方法的有效性和稳定性。此外，文档还列举了大量相关的科研方向和技术应用，涵盖智能优化算法、机器学习、电力系统、路径规划等多个领域，展示了该技术的广泛应用前景。; 适合人群：具备一定自动控制理论基础和Matlab编程能力的研究生、科研人员及工程技术人员，特别是从事智能控制、非线性系统控制及相关领域的研究人员； 使用场景及目标：①学习和掌握RBF神经网络与滑模控制相结合的自适应控制策略设计方法；②应用于电机控制、机器人轨迹跟踪、电力电子系统等存在模型不确定性或外界扰动的实际控制系统中，提升控制精度与鲁棒性； 阅读建议：建议读者结合提供的Matlab代码进行仿真实践，深入理解算法实现细节，同时可参考文中提及的相关技术方向拓展研究思路，注重理论分析与仿真验证相结合。
STM32F407-RT-Thread-CAN工程代码
12-18
STM32F407芯片，开发环境：RT-Thread Stdio开发环境，使用内部drv_can实现can功能，官方的drv_can.c文件中对于stm32f407的位时序配置错误，已修改位时序，但是800k的CAN速率，由于CAN时钟为42M的原因，无法整除(42/0.8=52.5)，导致800k的速率无法使用.
安卓应用源码Android闹钟源码
12-18
安卓应用源码Android 闹钟源码
转子轴承系统振动分析.zip
最新发布
12-18
1.版本：matlab2014a/2019b/2024b 2.附赠案例数据可直接运行。 3.代码特点：参数化编程、参数可方便更改、代码编程思路清晰、注释明细。 4.适用对象：计算机，电子信息工程、数学等专业的大学生课程设计、期末大作业和毕业设计。
oracle CREATE UNDO TABLESPACE
10-22
### 类型 在 Oracle 中，`CREATE UNDO TABLESPACE` 用于创建撤销表空间，它是一种特殊类型的表空间。撤销表空间主要用于存储事务修改数据之前的旧值，属于系统级别的存储结构，与用户数据、索引等存储在不同的表空间中。 ### 用途 - **事务回滚**：当事务执行 `ROLLBACK` 语句时，Oracle 可以利用撤销表空间中的旧数据将数据恢复到事务开始之前的状态。 - **读一致性**：保证用户在查询数据时，即使有其他事务正在修改这些数据，查询结果仍然是事务开始时的数据状态，避免了脏读等问题。 - **闪回查询**：支持用户查询过去某个时间点的数据，通过撤销表空间中的旧数据来实现。 ### 使用方法 创建撤销表空间的基本语法如下： ```sql CREATE UNDO TABLESPACE tablespace_name DATAFILE 'file_name' [ SIZE size_clause ] [ AUTOEXTEND [ON | OFF] [ NEXT next_clause ] [ MAXSIZE maxsize_clause ] ] [ EXTENT MANAGEMENT LOCAL [ UNIFORM SIZE size_clause ] ] [ SEGMENT SPACE MANAGEMENT { AUTO | MANUAL } ]; ``` 参数说明： - `tablespace_name`：撤销表空间的名称。 - `file_name`：指定撤销表空间的数据文件路径和名称。 - `SIZE size_clause`：指定数据文件的初始大小，例如 `SIZE 100M` 表示初始大小为 100MB。 - `AUTOEXTEND`：指定数据文件是否自动扩展，`ON` 表示自动扩展，`OFF` 表示不自动扩展。 - `NEXT next_clause`：当数据文件需要扩展时，每次扩展的大小。 - `MAXSIZE maxsize_clause`：数据文件允许扩展到的最大大小。 - `EXTENT MANAGEMENT LOCAL`：指定表空间采用本地管理方式，这是推荐的管理方式。 - `UNIFORM SIZE size_clause`：指定统一的区大小。 - `SEGMENT SPACE MANAGEMENT`：指定段空间管理方式，`AUTO` 表示自动管理，`MANUAL` 表示手动管理。 示例： ```sql CREATE UNDO TABLESPACE undotbs_02 DATAFILE '/u01/oracle/rbdb1/undotbs_02.dbf' SIZE 200M AUTOEXTEND ON NEXT 50M MAXSIZE 500M EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M SEGMENT SPACE MANAGEMENT AUTO; ```
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