Oracle vs SQL Server, 4k vs 16k block sizes I was reading over these 3 articles:

At my last company we only used MS SQL Server and MySQL, and if a server was strictly a database server we would setup the HDD to use 16k block sizes.

http://houseofbrick.com/improve-performance-as-part-of-a-sql-server-install/

I work for a different company running Oracle, we have a small issue every once in a while where the database will lock up for about 2 to 3 seconds when a query reads about 700K rows; we know it's a coding issue where a where statement needs to be added.

This article shows some metics for running 8k to 16k on various tables of size and weight:

http://blog.dbi-services.com/do-the-block-size-matter/

Then I read something very interesting:

http://www.dba-oracle.com/s_oracle_block_size.htm

Specifically here:

Block Size Advantages

Smaller blocksize:

-  Good for small rows with lots of random access.

Larger  blocksize:

-  Permits reading several rows into the buffer cache with a single I/O (depending on row size and block size).

Block Size Disadvantages

Smaller  blocksize:

- Not recommended for large rows. There might only be a few rows stored for each block, or worse, row chaining if a single row does not fit into a block.

Larger blocksize:

- Not good for index blocks used in an OLTP environment, because they increase block contention on the index leaf blocks.

Can I split up table reads and specify block size to use?

I thought block size is consistent across the disk and set when the drive is partitioned.

We have a 3-tier SAN, the Oracle server is virtual if that makes a difference.
Oracle logical block size is orthogonal to the storage logical block size (and the file system block size, for that matter). At a minimum your Oracle block size should be a multiple of the disk block size to avoid reading unnecessary data. If your tablespaces have different block sizes, the smallest of them (block sizes) would need to meet this constraint.