Re: DB_FILE_MULTIBLOCK_READ_COUNT question

The OS block size is more than likely 512b on your Solaris machine, not 8192b. The Oracle block size is usually set to a multiple of the OS block size. Most production databases on Solaris will use an 8192 oracle block size, some will use larger, few will use less.

I *want* to say your I/O block size is 32k or 64k, but I do not know how to determine that on Solaris (I'd ask the SA:-)

Anyway, what the DBA Handbook was explaining is that the multi_block_read_count parameter can't be set to 100 or something like that as the OS is limited to reading I/O block / Oracle block.

--
Dave A


"Michael J. Moore" <mNiOcShPaAeMl.j.moore_at_wcom.com> wrote in message
news:OVww5.1156$6a1.19316_at_pm01news.wcom.com...


> In the Oracle 8i DBA Handbook I am reading on page 335.:

>

> "The number of blocks read at a time is limited by the I/O buffer size of

> your operating system."

>

> The DB_BLOCKSIZE paramater in the init.ora is 8192 which means that the OS

> has an 8k disk block size (assuming that the DBA who set the parameter

 knew


> the disk block size and set a 1 to 1 ratio).

>

> But, what is the I/O buffer size of my OS. I am running Solaris on a Sun

> Enterprise II. Is there a command that I can type that will tell me what

 the


> I/O block size is?

>

> thanks,

> Mike

>