How to Disable Asynch_io on HP to Avoid Ioctl Async_config Error

How to Disable Asynch_io on HP to Avoid Ioctl Async_config Error Errno = 1 [ID 302801.1]
		修改時間 22-OCT-2009     型別 HOWTO     狀態 PUBLISHED

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Applies to:

Oracle Server - Enterprise Edition - Version: 9.2.0.1 to 11.1.0.7
HP-UX Itanium
HP-UX PA-RISC (64-bit)

Goal

How to disable async_io on Oracle in HP-UX to avoid this message in trace file:
Ioctl ASYNC_CONFIG error, errno = 1

Solution

If /dev/async is present and correctly configured, Oracle (for HP only) will use it for memory locking which is needed for async i/o for SGA memory pages via ioctl.

Oracle (for HP only) opens /dev/async successfully only if the /dev/async HP-UX device driver is properly configured for read and write.

This is irrespective of whether the DISK_ASYNC_IO parameter is set to TRUE.

Problem is Oracle (for HP only) still uses async I/O regardless of the value of init settings
(disk_asynch_io=FALSE and filesystemio_options=none).
The parameter filesystemio_options=none doesn't work.

From the 9.2 until 10.1 version, to inactivate ASYNCH_IO with Oracle, the workaround is to:

Note: This may impact other applications that wish to use asynch I/O

Grant dba group the MLOCK privilege to avoid the Ioctl ASYNC_CONFIG trace file errors:

Since the Oracle 10.2 version, the problem is resolved as these settings stop the tracing:
disk_asynch_io=FALSE
filesystemio_options=none