Database Rebuild

[ocp8]

Hello..

I am looking to rebuild my 80 gig database with an 8k block in the next couple of weeks and doing a reorg at the same time. I am implementing locally managed tablespaces with a uniform extent size. I would like to use the advice I found in the article "How to Stop Defragmenting and Start Living: The Definitive Word on Fragmentation". My question is what extent sizes to use? The article recommends 3 sizes: 128k, 4m & 128m. If I have a table that is 9 gig in size it would literally use thousands of extents using an initial and next of 128m. What sizes would be the best to use? I have tables ranging from 260k to 9g. Thank you for your advice!!

[marist89]

I'm not sure how you round, but I wouldn't group 72 in with "thousands".

9*1024/128=72

[gandolf989]

Given an 80gb database you probably want your extent sizes to be larger than 8k. 16k or 32k extent sizes wouldn't be unreasonable. If you choose to make them larger it would be because you know that your database reads data in large chunks.

[marist89]

Originally posted by gandolf989
If your 9gb tables were in tablespaces that had 512mb uniform extents then they would have around 180 extents each.

Check your math on that one. 9/.5 = 18.

[gandolf989]

I did and realized you had a simpler way of showing the number of extents. Thanks for mentioning it.