This system variable can be specified as a command-line argument to mysqld or it can be specified in a relevant server option group in an option file. For example:.
This system variable defaults to the file ibdata1 , and it defaults to a minimum size of 12M , and it defaults with the autoextend attribute enabled. InnoDB defaults to allocating 12M to the ibdata1 file for the system tablespace. While this is sufficient for most use cases, it may not be for all. You may find after using MariaDB for a while that the allocation is too small for the system tablespace or it grows too large for your disk.
Fortunately, you can adjust this size as need later. In cases where you need a larger system tablespace, add the autoextend option to the last value.
Under this configuration, when the last system tablespace grows beyond the size allocation, InnoDB increases the size of the file by increments. In cases where the InnoDB system tablespace has grown too large, the process to reduce it in size is a little more complicated than increasing the size.
For each partition, we need to do the following process:. If you do not have the tablepace's. When this process is complete for all partitions, the target table will contain the imported data:. MariaDB If a file-per-tablespace file contains columns that use one or more of these temporal data types and if the tablespace file's original table was created with a certain storage format for these columns, then the tablespace file can only be imported into tables that were also created with the same storage format for these columns as the original table.
Otherwise, you will see errors like the following:. InnoDB file-per-table tablespaces can use different row formats. If a file-per-tablespace file was created with a certain row format, then the tablespace file can only be imported into tables that were created with the same row format as the original table.
The error message will be a bit more descriptive in MariaDB Be sure to check a tablespace's row format before moving it from one server to another. So when importing tablespaces, referential integrity can only be guaranteed to import all tables bound by foreign key constraint at the same time, from an EXPORT of those tables taken with the same transactional state.
When enabled, the Server encrypts data before writing it to the tablespace and decrypts reads from the tablespace before returning result-sets. This means that a malicious user attempting to exfiltrate sensitive data won't be able to import the tablespace onto a different server as shown above without the encryption key. Knowledge Base Contact Login Search. For information about configuring additional undo tablespaces, see Section The global temporary tablespace stores rollback segments for changes made to user-created temporary tables.
The initial file size is slightly larger than 12MB. The file size or combined file size must be slightly larger than 12MB. In MySQL 8. From MySQL 8. A fully qualified path or path relative to the data directory is permitted.
This value is set when the instance is created and remains constant afterward. Alternatively, you can specify page size in bytes , , , , The default 16KB page size is appropriate for a wide range of workloads, particularly for queries involving table scans and DML operations involving bulk updates.
Smaller page sizes might be more efficient for OLTP workloads involving many small writes, where contention can be an issue when a single page contains many rows. Smaller pages can also be more efficient for SSD storage devices, which typically use small block sizes. Keeping the InnoDB page size close to the storage device block size minimizes the amount of unchanged data that is rewritten to disk.
MySQL allocates memory to various caches and buffers to improve performance of database operations. When allocating memory for InnoDB , always consider memory required by the operating system, memory allocated to other applications, and memory allocated for other MySQL buffers and caches. Buffers specific to InnoDB are configured using the following parameters:.
The default buffer pool size is MB. For additional guidance, see Section 8. For information about how to configure InnoDB buffer pool size, see Section Buffer pool size can be configured at startup or dynamically. On systems with a large amount of memory, you can improve concurrency by dividing the buffer pool into multiple buffer pool instances.
By default, InnoDB creates one buffer pool instance. The number of buffer pool instances can be configured at startup. For more information, see Section The default size is 16MB. A large log buffer enables large transactions to run without writing the log to disk before the transactions commit. For related information, see Section 8. It is a risk if the memory allocated to the mysqld process for global and per-thread buffers and caches is close to or exceeds 2GB.
You may need to modify the formula to account for buffers and caches in your MySQL version and configuration. On Linux, if the kernel is enabled for large page support, InnoDB can use large pages to allocate memory for its buffer pool.
See Section 8. Testing and Benchmarking with InnoDB. InnoDB Multi-Versioning. Creating Tables Externally. Clustered and Secondary Indexes. The System Tablespace. File-Per-Table Tablespaces. Temporary Tablespaces. Disabling Tablespace Path Validation. Optimizing Tablespace Space Allocation on Linux. InnoDB Transaction Model. Transaction Isolation Levels. Consistent Nonlocking Reads. How to Minimize and Handle Deadlocks. Transaction Scheduling. InnoDB Startup Configuration. Configuring Multiple Buffer Pool Instances.
Making the Buffer Pool Scan Resistant. Configuring Buffer Pool Flushing. Saving and Restoring the Buffer Pool State.
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