Re: What is a good blocksize to use.

From: ben brugman <ben_at_niethier.nl>
Date: Wed, 25 Sep 2002 22:43:43 +0200
Message-ID: <amt75v$4mc$1@reader12.wxs.nl>

I am trying to get to grips with different blocksizes. I do have a load of books and manuals. But can not find a complete argumentation for using certain blocksizes.

What I am actually trying to find out what does the blocksize do while a block is migrating from the disk through a RAID device through the operating system and then finally through Oracle.
More specific if the size's are not the same.

The disk does have some cache.
The OS does have cache but is it used ?
And Oracle controls some 'cache'.

If the sizes differ, how is this handled.

Example RAID stripes of 64 K
OS blocks of 32 K
Oracle blocks of 16 K.

Oracle request a 16 K block what happens ? (Which is not in any cache).
If the next 16 K block is requested what happens ?

Oracle writes a 16 K block what happens ? Does the raid device have to write a hole stripe ? If so where does it get the rest of the information ?

ben brugman Received on Wed Sep 25 2002 - 15:43:43 CDT