20221121 | Bug fixes: The bug due to which the reference to a temporary table cannot be properly applied to a common table expression (CTE) when you perform a query by using the CTE in some scenarios is fixed. |
20220830 | |
20220730 | Performance improvements: The Buffer Pool Free Resize feature is optimized. |
20220530 | - New features:
- If your database system consists of only one RDS instance that uses standard SSDs or enhanced SSDs (ESSDs), redo logs can be used to perform incremental backups and restore data to any point in time.
- The Persist Binlog Into Redo V2 feature is supported. High concurrency capabilities are optimized to provide better performance.
- The SSL encryption feature is optimized, and some bugs are fixed.
- The permissions to manage the sys or performance_schema database are revoked from standard accounts.
- The
FLUSH TABLES WITH READ LOCK and UNLOCK TABLES logs are added to error logs, which enables online troubleshooting.
- Performance improvements:
- The performance of buffer pool initialization is improved.
- During the recovery from a system downtime, the rollback method of pending transactions is changed from synchronous rollback to asynchronous rollback to improve the recovery time objective (RTO).
- The memory usage and update speed of the adaptive hash index (AHI) is optimized.
- Bidirectional circular replication is optimized. When a secondary RDS instance sends binary logs to its primary RDS instance, the secondary RDS instance skips transactions that belong to the primary RDS instance. This reduces the network traffic of circular replication.
- The time to recover from an instance downtime is reduced.
- Bug fixes:
- The bug that the mysql.events table fails to be migrated during an upgrade from MySQL 5.7 to MySQL 8.0 is fixed.
- The bug that may cause a system downtime when a full-text index table is deleted during an upgrade from MySQL 5.6 to MySQL 8.0 is fixed.
- The bug that a system downtime may occur due to high Mini Drive-Lock (MDL) competition is fixed.
- The bug that causes xengine_record parsing errors is fixed.
- The bug that causes compression failures when X-Engine creates indexes is fixed.
- The data in the start_time column of the slow_log table is amended.
- The compilation speed is improved. Compilation warnings are fixed.
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20220523 | Bug fixes:- The bug that the execution speed of the
SELECT COUNT(*) statement without the WHERE clause is slow is fixed. - The bug that the system fails because the stored procedures with the
WITH ROLLUP modifier are called multiple times is fixed.
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20220331 | - New features:
- If the value of
innodb_buffer_pool_size is less than 1 GB, the value of innodb_buffer_pool_instances can be greater than 1. - If the Native flashback feature is enabled for an RDS instance, the impact on the performance of the RDS instance is reduced.
- Bug fixes:
- The bug that causes the
Unknown thread id message to be displayed when you kill a session is fixed. - The bug that the settings of the rds_expose_priv_list parameter do not take effect after an RDS instance restarts is fixed.
- The bug that the Binlog in Redo feature blocks the checkpoint push is fixed.
- The fixes for Bug#33341080 and Bug#32962511 in MySQL 8.0.25 of MySQL Community Edition are incorporated.
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20210930 | - New features:
- Bug fixes:
- The bug due to which the execution result of the
SHOW GLOBAL STATUS statement is abnormal is fixed. - The bug due to which an RDS instance cannot start when the profiling feature of JeMalloc is enabled for the RDS instance is fixed.
- The bug due to which an RDS instance for which the sequence feature is enabled unexpectedly exits when the
INSERT INTO SELECT statement is executed is fixed. - The
dbms_recycle.restore_table permission is removed. - The number of index scans is added to the
I_S.INDEX_STATISTICS table. - More metrics that are used to measure the performance of an RDS instance are added to the
I_S.PERF_STATISTICS table. - The bug that affects the performance of an RDS instance when the user-defined function
nextval or currval conflicts with the system function SEQUENCE on the RDS instance is fixed. - The bug due to which X-Engine cannot immediately respond to
KILL SESSION requests is fixed. - The bug that causes inconsistency errors if specific DDL operations fail in extreme circumstances is fixed.
- The bug that causes a stack overflow is fixed by using a protection mechanism.
- The bug that prevents the mysqld program from starting when the Binlog in Redo feature and
X-Engine are used at the same time is fixed. A system variable named persist_binlog_to_redo is used to specify whether to enable the Binlog in Redo feature. - The bug that causes memory leaks when the
pthread_getattr_np function is invoked is fixed. - The bug due to which ApsaraDB RDS deletes cached pages that are generated by the
performance agent feature is fixed. - The bug of the Statement outline feature is fixed.
- The bug due to which ApsaraDB RDS resets the used session tracker when errors occur during the execution of statements is fixed.
- The
ccl_wait_timeout variable is renamed. - The bug that prevents ApsaraDB RDS from deleting socket files when the database process stops is fixed. This bug prevents the database process from starting.
- The priorities of the user-defined functions nextval and currval are adjusted.
- The bug due to which the
net_length_size function returns error 251 is fixed.
Note Open source MySQL 8.0.22 provides the derived_condition_pushdown feature. The feature can reduce the amount of data scanned in derived tables and accelerate queries. However, the feature ignores user variables. As a result, null values are returned for user variables, and queries cannot be completed. For more information, see the official MySQL documentation. To resolve this issue, you must connect to their RDS instance and run the set optimizer_switch="derived_condition_pushdown=off"; command to disable the feature. For more information, see Use a database client or the CLI to connect to an ApsaraDB RDS for MySQL instance. |
20201031 | |
20200831 | - New features:
- The innodb_parallel_read_threads parameter is added to specify whether to allow the
count(*) function to run scans in parallel. If this parameter is set to 0 , this function cannot run scans in parallel. For more information, see Modify the parameters of an ApsaraDB RDS for MySQL instance. - Start global transaction identifiers (GTIDs) and end GTIDs are supported by the mysqlbinlog plug-in.
- Log sequence numbers (LSNs) are supported in the redo log.
- innodb_lsn: the LSN of each record in the redo log.
- innodb_log_checkpoint_lsn: the LSN of the last checkpoint.
- innodb_log_write_lsn: the LSN of each record that is written to the redo log.
- innodb_log_ready_for_write_lsn: the LSN of the last record that is written to the log buffer.
- innodb_log_flush_lsn: the LSN of each record that is flushed from the redo log to the disk.
- innodb_log_dirty_pages_added_up_to_lsn: the LSN of each record that logs a page as dirty.
- innodb_log_oldest_lsn: the LSN of each record that logs an update to a page.
- Performance improvements:
- The CCL feature is optimized to schedule and concurrently run transactions in a more efficient manner.
- The CCL feature is optimized to prioritize stored procedures in a more efficient manner.
- Bug fixes:
- The bug due to which the recursively called interpreter does not check the memory size is fixed.
- The bug due to which table definitions cannot be modified when Transparent Data Encryption (TDE) is enabled is fixed.
- The bug due to which the event scheduler causes memory leaks is fixed.
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20200630 | - New features:
- The faster DDL feature is supported. This feature provides an optimized buffer pool management mechanism to reduce the impacts of DDL operations on database performance and to increase the number of online DDL operations that can be concurrently run. For more information, see Faster DDL.
- The maximum number of connections that are allowed is increased to 500,000.
- Performance improvements:
- The thread pool feature is optimized.
- The memory allocation mechanism is optimized. You can specify the maximum memory consumption that is allowed for PERFORMANCE SCHEMA based on the instance type.
- Audit log files are no longer analyzed.
- TDE is optimized to cache the keys that are provided by Key Management Service (KMS).
- The statuses of threads that are managed by the CCL feature are renamed. For more information, see Statement concurrency control.
- Bug fixes:
- The bug due to which ApsaraDB RDS considers semicolons (;) as part of the statements that are used to create outlines is fixed.
- The bug due to which an RDS instance unexpectedly exits when tables are modified is fixed.
- The bug due to which earlier versions do not support the keywords that are supported in later versions is fixed. The keywords are memory and array.
- The bug due to which ApsaraDB RDS incorrectly counts the number of waits when commands are read from a database client is fixed.
- The bug that causes failures in updating the minor engine version of an RDS instance is fixed.
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20200430 | - New features:
- The Binlog in Redo feature is supported. This feature allows ApsaraDB RDS to write binary log records to the redo log before the binary log records are flushed to the disk. This reduces the consumption of I/O resources and improves database performance. For more information, see Binlog in Redo.
- A restructured row caching mechanism is supported for X-Engine.
- The XA_RECOVER_ADMIN permission is supported.
- Performance improvements:
- The code that is used to scan data when operations are performed on a temporary InnoDB table is optimized. This allows ApsaraDB RDS to scan only dirty pages rather than all pages in the buffer pool.
- The global parameter opt_readonly_trans_implicit_commit is renamed as rds_disable_explicit_trans to ensure compatibility with MySQL 5.6.
- The upgrades to an RDS instance are no longer recorded by the audit log feature.
- The memory resources that are consumed by DDL operations on X-Engine tables are reduced.
- Bug fixes:
- The bug due to which the sizes of X-Engine tables on the disk are inconsistent with the statistics in the INFORMATION_SCHEMA database is fixed.
- The bug due to which ApsaraDB RDS initializes X-Engine logs when the error log file is re-opened is fixed.
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20200331 | - New features:
The TRUNCATE TABLE statement is supported. After the statement is executed on a table, ApsaraDB RDS moves the table to a dedicated directory that is used for the recycle bin, and then creates a table that uses the same schema as the truncated table. For more information, see Recycle bin. - Performance improvements:
- The output of TCP errors is disabled by default.
- The thread pool feature is optimized to provide higher performance when the default configurations are used.
- Bug fixes:
- The bug that causes invalid databases and tables is fixed. This bug is triggered when the names of partitioned tables are separated by the combination of a pound key and a letter p (
#p ). - The bug due to which CCL-managed statements are case-sensitive is fixed.
- The updates to the features in open source MySQL 8.0.17 and MySQL 8.0.18 are incorporated. For more information, see Changes in MySQL 8.0.17 and Changes in MySQL 8.0.18.
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20200229 | - New features:
- The performance agent feature is supported. For more information, see Performance Agent. This feature is provided as a MySQL plug-in. This feature allows ApsaraDB RDS to compute and analyze the metrics that are used to measure the performance of an RDS instance.
- A metric is provided to measure the round trip time over the network. This metric helps you monitor the performance of an RDS instance that runs in semi-synchronous mode.
- Online DDL operations are supported by X-Engine.
- Performance improvements:
- The CCL feature is optimized to control the concurrency of statements on read-only RDS instances.
- The outline feature is optimized to support outlines on secondary RDS instances.
- The database proxy feature is enhanced to optimize short-lived connections.
- The amount of time that is required to execute the PAUSE statement is reduced in various CPU architectures.
- A memory summary table is added to provide the statuses of thread pools.
- Bug fixes:
- The bug due to which ApsaraDB RDS forbids the ppoll function and replaces the ppoll function with the poll function is fixed. This bug is found in Linux kernel versions earlier than 4.9.
- The bug that causes errors when the wrap_sm4_encrypt function is invoked is fixed.
- The bug due to which ApsaraDB RDS locks global variables during the rotation of audit logs is fixed.
- The bug that causes errors during restoration inconsistency checks is fixed.
- The bug that causes inaccurate time values in the io_statistics table is fixed.
- The bug due to which an RDS instance unexpectedly exits when invalid compression algorithms are used is fixed.
- The bug that causes user columns in MySQL 8.0 and MySQL 5.6 to be incompatible is fixed.
- Optimized programs:
- The faster DDL feature is supported. This feature provides an optimized buffer pool management mechanism to reduce the impacts of DDL operations on database performance and to increase the number of online DDL operations that can be concurrently run. For more information, see Faster DDL.
- The thread pool feature is optimized to improve database performance.
- The mechanism that is used for reference counting is optimized to prevent memory leaks in buffers.
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20200110 | - New features:
Three hints are added. These hints can be used in the following statements to commit transactions and roll transactions back at high speeds: SELECT, UPDATE, INSERT, and DELETE. This increases the throughput of applications. For more information, see Inventory Hint. - Performance improvements:
- The CCL feature is optimized. When an RDS instance starts, CCL queue structures are initialized before CCL rules are initialized.
- The file deletion mechanism is optimized. When ApsaraDB RDS asynchronously deletes files, the links to small files are removed.
- The thread pool feature is optimized. For more information, see Thread Pool.
- The restoration inconsistency check feature is disabled by default.
- The permissions that are required to configure variables are changed.
- Standard accounts can be granted the permissions to configure the following variables:
- auto_increment_increment
- auto_increment_offset
- bulk_insert_buffer_size
- binlog_rows_query_log_events
- Superuser accounts and system variable administrators can be granted the permissions to configure the following variables:
- binlog_format
- binlog_row_image
- binlog_direct
- sql_log_off
- sql_log_bin
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20191225 | |
20191115 | New features: The statement queue feature is supported. This feature allows statements to be queued in the same bucket. These statements can be executed on the same resources. For example, these statements can be executed on the same row of a table. This feature helps reduce the overhead that is caused by conflicts. For more information, see Statement Queue. |
20191101 | - New features:
- The SM4 encryption algorithm is supported for TDE. For more information, see Configure TDE for an ApsaraDB RDS for MySQL instance.
- Data protection is supported for secondary RDS instances. Only the accounts that have the SUPER permission or the REPLICATION_SLAVE_ADMIN permission are authorized to insert, delete, and modify data in the slave_master_info, slave_relay_log_info, and slave_worker_info tables.
- A mechanism is provided to increase the priorities of auto-increment keys. If a table does not have a primary key or the table does not have a unique key without a null value, the auto-increment key without a null value is assigned the highest priority.
- A mechanism is provided to prevent the automatic conversion of tables from the MEMORY storage engine to the MyISAM storage engine. These tables include system tables and the tables that are called by threads in the initializing state.
- A mechanism is provided to flush binary log records to the disk before redo log records.
- A mechanism is provided to stop the creation of temporary tables on an RDS instance when the RDS instance is locked.
- X-Engine that is based on a log-structured merge (LSM) tree is provided to store transactions.
- Performance improvements:
- The thread pool feature is optimized to reduce mutual exclusions (mutexes). For more information, see Thread Pool.
- The performance insight feature is optimized to monitor thread pools. For more information, see Performance Insight.
- The following parameters are adjusted:
primary_fast_lookup : a session parameter. The default value is true. thread_pool_enabled : a global parameter. Default value: true.
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20191015 | - New features:
- The TDE feature is provided to support real-time I/O encryption and decryption of data files. This feature encrypts data before the data is written to the disk and decrypts data before the data is read from the disk and written to the memory. For more information, see Configure TDE for an ApsaraDB RDS for MySQL instance.
- The returning feature is provided. This feature allows DML statements to return result sets. The DBMS_TRANS package is provided for you to use this feature with ease. For more information, see Returning.
- Forced conversion from the MyISAM or MEMORY storage engine to the InnoDB storage engine is supported. If the global variable force_mysiam_to_innodb or force_memory_to_innodb is set to ON, tables are automatically converted from the MyISAM or MEMORY storage engine to the InnoDB storage engine when the tables are created or modified.
- A mechanism is provided to prevent accounts that are not privileged accounts from performing primary/secondary switchovers. Only privileged accounts are granted the permissions to perform primary/secondary switchovers.
- A performance proxy plug-in is provided. This plug-in obtains performance data and saves the data as TXT files to on-premises computers. A round-robin algorithm is used to retain only the most recent files that contains performance data at the single-digit second level.
- A timeout period can be configured for mutexes in InnoDB. You can change the timeout period by using the global variable innodb_fatal_semaphore_wait_threshold. The default value of the global variable is 600.
- Index hint errors can be ignored. You can configure an RDS instance to ignore index hint errors by using the global variable ignore_index_hint_error. The default value of the global variable is false.
- The SSL encryption feature can be disabled. For more information, see Configure SSL encryption for an ApsaraDB RDS for MySQL instance.
- The output of TCP errors is supported. TCP read, read-wait, and write-wait errors are returned together with error codes in end_connection events. Log records that contain the information about the errors are also generated.
- Bug fixes:
- The bug due to which a Linux operating system cannot merge local asynchronous I/O (AIO) requests before linear Read Ahead is triggered is fixed.
- The bug due to which ApsaraDB RDS inaccurately collects statistics about tables and indexes is fixed.
- The bug that prevents direct access to the primary key index of a table when a primary key is specified for the table is fixed.
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20190915 | Bug fixes: The bug that causes memory leaks when the Cmd_set_current_connection process runs is fixed. |
20190816 | - New features:
- The thread pool feature is provided to separate threads from sessions. If a large number of sessions are created, ApsaraDB RDS can run a small number of threads to complete the tasks in active sessions. For more information, see Thread Pool.
- The CCL feature is supported. You can specify the maximum number of concurrent requests that are allowed for an RDS instance. This way, the RDS instance can handle traffic bursts, process statements that consume an excessive number of resources, and adapt to the changes in SQL models. The CCL feature helps ensure the continuity and stability of RDS instances. For more information, see Statement concurrency control.
- The statement outline feature is provided to support optimizer hints and index hints. These hints are used to ensure that ApsaraDB RDS can run query plans in a stable manner. For more information, see Statement outline.
- The Sequence engine is provided to simplify the generation of sequence values. For more information, see Sequence Engine.
- The Purge Large File Asynchronously feature is provided to asynchronously delete files. Before a tablespace is deleted, ApsaraDB RDS renames the files in the tablespace as temporary files. Then, ApsaraDB RDS starts background threads to asynchronously delete the temporary files. For more information, see Purge Large File Asynchronously.
- The performance insight feature is provided to support load monitoring, association analysis, and performance optimization at the instance level. This feature allows you to evaluate the loads on an RDS instance and troubleshoot performance issues. This way, the stability of the RDS instance can be ensured. For more information, see Performance Insight.
- An optimized instance locking mechanism is provided. This mechanism allows you to drop or truncate tables on an RDS instance even if the RDS instance is locked.
- Bug fixes:
- The bug due to which ApsaraDB RDS incorrectly calculates file sizes is fixed.
- The bug due to which irrelevant processes can reuse idle memory resources is fixed.
- The bug due to which a host unexpectedly exits when the available cache size on the host is 0 is fixed.
- The bug that causes conflicts between implicit primary keys and CTS statements is fixed.
- The bug due to which ApsaraDB RDS incorrectly generates logs for slow queries is fixed.
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20190601 | - Performance improvements:
- Metadata locking on logging tables is reduced.
- The code for termination options is restructured.
- Bug fixes:
- The bug due to which precompiled statements are not recorded by the audit log feature is fixed.
- The bug due to which ApsaraDB RDS cannot mask error log records in logging tables when the names of the logging tables are invalid is fixed.
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