Re: why does db_block_buffers always show 0

On Mon, 18 Aug 2003 22:07:47 +0200, Sybrand Bakker <gooiditweg_at_sybrandb.demon.nl> wrote:

> On Mon, 18 Aug 2003 19:28:11 GMT, "Anurag Varma"
> <avarmadba.skipthis_at_yahoo.com> wrote:
>
>> And: if you just set db_block_buffers, then it should come into effect
>> (Have
>> not tried it,
>> but documentation seems to state that).
>
>
> It does, but you will be basically running 8i memory management, so
> you can't change your SGA dynamically.
>
>
> Sybrand Bakker, Senior Oracle DBA
>
> To reply remove -verwijderdit from my e-mail address
>

There'll also be a dirty great warning flashed at you immediately you issue the startup command reminding you that you are using deprecated parameters. It will still open, but the warning is a bit disconcerting, to say the least.

Interesting that you say "you can't change your SGA dynamically", because it's actually still true in 9i that you can't change your SGA dynamically, either. Oh, you can certainly *re-distribute* memory between the various caches on-the-fly, but the total amount of SGA is utterly fixed at whatever SGA_MAX_SIZE is set to (or computed to be if it's not explicitly set), and SGA_MAX_SIZE itself cannot be modified dynamically. A cunning piece of Oracle marketing, I think, calling the ability to alter the size of a few caches 'dynamic SGA'.

By the way: to Daniel... Undo tablespaces do not have to be of the db_block_size size, but can be of any of the non-standard sizes. TEMP however, must be db_block_size (as must SYSTEM, as you said).

Regards
HJR Received on Mon Aug 18 2003 - 16:10:58 CDT