Block Size Vs OS Block Size

[ckwan]

Hi,
I am just wonder everytime I read the book, saying the block size created must able to divide by OS block Size ? How to find out from my OS block Size (NT/ Windows 2000) ? Is there any relationships between these two types of block?

Thanks.

[Rookie]

[QUOTE][i]Originally posted by ckwan [/i]
[B]Hi,
I am just wonder everytime I read the book, saying the block size created must able to divide by OS block Size ? How to find out from my OS block Size (NT/ Windows 2000) ? Is there any relationships between these two types of block?

Thanks.
[/B][/QUOTE]

Oracle has two block sizes (one that is part of the Physical database called an OS block which is larger than an Oracle Block in Memory (Logical Space). The Oracle Block size is found under DB_Block_Size initialization parameter which is only set at database creation time. These logical Oracle blocks are made up of O/S blocks. That's all you need to know!

Show parameter DB_BLOCK_SIZE is the command to look up the size as Oracle Blocks are made up of O/S blocks. I imagine that Microsoft databases also consist of similar memory structures.

Hope this helps...rookie

[ckwan]

Hi, thanks for the reply but what I want to know is how to find out the OS Block like NT server. How do I know what is my OS Block size available, is it 512 or 1024 KB or more ?

Thanks

[drishti]

hi,
NT block size is 2k,your oracle block size can be a multiple of it,2k,4k,8k etc.

hope this helps,and see some NT books to know about block size.

[puneet]

Hi

The OS block size can be found by df -g command onn prompt.The oracle block size has to be a nmultiple of the OS block size to improve efficeieny and maintain consistency. Well, This is what is recommeneded.

Thanks