Re: db_file_multiblock_read_count and 10g

>
>
> IIRC _db_file_exec_read_count=8 and
> _db_file_optimizer_read_count=((max I/O size)/DB_BLOCK_SIZE)), so
> usually 1MB I/O size.



I think you mean _db_file_optimizer_read_count=8 and
_db_file_exec_read_count = ((max I/O size)/DB_BLOCK_SIZE)).

This is a reasonable assumption, but I'm not sure how Oracle determines the
maximum I/O size. On my laptop, Oracle 10.2.0.1 and 11.1.0.6 show quite
different _db_file_exec_read_count.

In 10.2.0.1 : _db_file_exec_read_count = 5
In 11.1.0.6 : _db_file_exec_read_count = 128

It seems quite dependent on Oracle version, not just on OS and/or storage
settings.


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