Re: Is DB_FILE_MULTIBLOCK_READ_COUNT a dynamic parameter?

Axel Schlueter wrote:
>
> Hi experts,
>
> I have a question concerning the INIT.ORA Parameter
> DB_FILE_MULTIBLOCK_READ_COUNT (DFMRC). In an announcement for Version 7.3,
> ORACLE said that this parameter would be dynamic, i.e. you could change it
> using the ALTER SYSTEM command.
>
> Now, I'm using Version 7.3.2 on Solaris 2.4, but I don't find any
> documentation about this feature. There's no
>
> ALTER SYSTEM SET DB_FILE_MULTIBLOCK_READ_COUNT
>
> in the SQL reference, nothing in the server administration guide or the
> READMEs. The migration guide lists all dynamic INIT.ORA paramters --- no
> DFMRC there.
>
> But I can use the command
>
> ALTER SYSTEM SET DB_FILE_MULTIBLOCK_READ_COUNT = 16
>
> The value is changed in V$PARAMETER and the whole thing seems to work.
>
> Any ideas if dynamic DFMRC does not belong to the production release?
> Any experiences with different versions/OS?
>
> Any help appreciated.
>
> TIA
>
> Axel Schlueter
> schluete_at_informatik.uni-hannover.de
> Universitaet Hannover, Germany

Hi, I have a separate comment/question about DFRMC

The example init.ora, and the manuals give the range of values for this parameter to be between 8 and 32. However, the default is based on DB_BLOCK_BUFFERS and PROCESSES. I commented out the explicit setting (of 20) in my init.ora and found the calculated value to be in the range 300 to 1000+ when restarting the database, what gives? Are these useful values, and if so, why does the documentation suggest the much smaller range?

Thanks. Received on Thu Dec 05 1996 - 00:00:00 CET