Oracle 参数 TAPE_ASYNCH_IO 官方解释，作用，如何配置最优化建议
本站中文解释
TAPE_ASYNCH_IO 是一个 Oracle 参数，主要用于 Oracle 是否使用异步 I/O，默认值为 TRUE，允许利用操作系统异步I/O功能使用磁带端口。
如何正确设置：
1. 识别系统操作系统是否支持异步 I/O 功能。
2. 设置TAPE_ASYNCH_IO 为TRUE 并在 Oracle 中打开 TAPE_ASYNCH_IO 选项。
3. 调整 Oracle 参数db_file_multiblock_read_count 为适当值，以便尽量地减少 I/O 次数，提高数据库上传或下载数据的速度。
4. 确保与磁带设备的连接正确无误，以确保 Oracle 能够正常的传输数据。
官方英文解释
TAPE_ASYNCH_IO controls whether I/O to sequential devices (for example, backup or restore of Oracle data to or from tape) is asynchronous—that is, whether parallel server processes can overlap I/O requests with CPU processing during table scans.
| Property | Description |
|---|---|
|
Parameter type |
Boolean |
|
Default value |
|
|
Modifiable |
No |
|
Modifiable in a PDB |
No |
|
Range of values |
|
|
Basic |
No |
If your platform supports asynchronous I/O to sequential devices, Oracle recommends that you leave this parameter set to its default. However, if the asynchronous I/O implementation is not stable, you can set TAPE_ASYNCH_IO to false to disable asynchronous I/O. If your platform does not support asynchronous I/O to sequential devices, this parameter has no effect.
See Also:
Oracle Database VLDB and
Partitioning Guide for more information about this parameter
