Product manual

Galaxy G3G12 / G3G16 - Installation and Hardware Reference Manual
229 Section 7 Technology Background
7.3 Choosing Stripe Size
Stripe Size, also called “Stripe Block Size”, refers to the size of the data blocks written to, and read from, the
physical drives. Stripe Size is specified when you create a disk array. In order to change the Stripe Size of
an existing disk array, you must delete the disk array and create a new one. You can select Stripe Size
directly when you use the Advanced function to create a disk array. If you use the Express function to create
a disk array, GAM selects the Stripe Size when you choose an Application Type.
The available Stripe Sizes are 64, 128, 256 KB, 512 KB, and 1 MB. 64 KB is the default. There are two
issues to consider when selecting the Stripe Size.
First, you should choose a Stripe Size equal to, or smaller than, the smallest cache buffer found on any
physical drive in the disk array. Selecting a larger value slows read/write performance because physical
drives with smaller cache buffers need more time for multiple accesses to fill their buffers.
Second, if your data retrieval consists of fixed data blocks, such as with some database or video
applications, then you should choose that size as your Stripe Size.
If you do not know the cache buffer or fixed data block sizes, we suggest you select 64 KB as your Stripe
Size. Generally speaking, email, POS, and webservers prefer smaller stripe sizes. Video and database
applications prefer larger stripe sizes.