Oracle ORACLE9I B10508-01, Руководство по установке

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HP OpenVMS Alpha SYSGEN Parameters
CD-ROM Pre-installation Requirements 3-13
HP OpenVMS Alpha SYSGEN Parameters
For instructions on calculating MIN_GBLPAGES, MIN_GBLSECTIONS, and
MIN_MAXBOBMEM, refer to the READMEVMS.DOC in the RDBMS directory.
Using the Reserved Memory Registry
Through its interface within the SYSMAN utility, the Reserved Memory Registry
allows an HP OpenVMS Alpha system to be configured with large amounts of
memory set aside for use within memory-resident global sections
.
The AUTOGEN
utility considers the pre-allocated reserved memory when it tunes the system.
The advantages to reserving memory for an SGA are as follows:
■
You can be certain that the memory is available and that the system is correctly
tuned.
■
The memory is reserved at boot time as contiguous aligned physical pages
.
This allows the system to optimize the mapping of the SGA.
■
The memory is pre-allocated and zeroed
.
This results in faster SGA mapping
and faster instance startup.
To reserve memory for an SGA, use the SYSMAN utility
.
The size qualifier is
specified in megabytes
.
For example, to reserve memory for a 6 GB SGA for the
SID named TEST, use the following commands:
$ MCR SYSMAN
SYSMAN> RESERVED_MEMORY ADD ORA_TEST_SGA/SIZE=6144/ALLOCATE/ZERO/PAGE
SYSMAN> EXIT
Then run AUTOGEN and reboot the system to allow AUTOGEN to adjust other
system parameters for the reduced amount of memory that is available to the rest of
the system.
Memory for multiple SGAs may be reserved
.
Any change to the name or size of a
piece of reserved memory may require rebooting the system
.
During instance
startup, Oracle server compares the size of the reserved memory, if any, with the
size of the SGA
.
If appropriate, one of the following messages will be included in
the Alert log:
Note: 1 GB = 1024 MB