OCP-1Z0-053-V12.02-48题

48.View the Exhibit to examine the error obtained during the I/O calibration process. There are no data

files on raw devices. What is the reason for this error?

A. The DISK_ASYNCH_IO parameter is set to TRUE.

B. The FILESYSTEMIO_OPTIONS parameter is set to NONE.

C. Another session runs the I/O calibration process concurrently.

D. The pending area has not been created before running the I/O calibration process.

Answer: B

答案解析：

参考：http://docs.oracle.com/cd/E11882_01/server.112/e41573/os.htm#PFGRF94412

查看图表检查在I/ O校准过程中得到的错误。在裸设备上没有数据文件。此错误的原因是什么？

You can use the  FILESYSTEMIO_OPTIONS   initialization parameter to enable or disable asynchronous I/O or direct I/O on file system files. This parameter is platform-specific and has a default value that is best for a particular platform.

FILESYTEMIO_OPTIONS can be set to one of the following values:

• ASYNCH: enable asynchronous I/O on file system files, which has no timing requirement for transmission.

• DIRECTIO: enable direct I/O on file system files, which bypasses the buffer cache.

• SETALL: enable both asynchronous and direct I/O on file system files.

• NONE: disable both asynchronous and direct I/O on file system files.