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Stripe size, Sector size, Preferred controller id – Promise Technology 2-Year Extended Warranty for VessR2000 RAID Head User Manual

Page 605: Tripe, Ector, Referred, Ontroller

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578

Vess R2000 Series Product Manual

Promise Technologies

s

tripe

s

ize

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 logical drive. You can choose Stripe Size directly when

you use the Wizard Advanced Configuration function to create a logical drive.

You cannot change the Stripe Size of an existing logical drive. You must delete the logical drive and create a

new one.

The available Stripe Sizes are 64 KB, 128 KB, 256 KB, 512 KB, and 1 MB. 64 KB is the default. There are two

issues to consider when choosing the Stripe Size:

• 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.

• If your data retrieval consists of fixed data blocks, such as with some data-base 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, choose 64 KB as your Stripe Size. Generally

speaking,

• Email, POS, and web servers prefer smaller stripe sizes.

• Video and database applications prefer larger stripe sizes.

s

ectOr

s

ize

A sector is the smallest addressable area on a physical drive. Sector size refers to the number of data bytes a

sector can hold. A smaller sector size is a more efficient use of a physical drive’s capacity. 512 bytes (512 B) is

the most common sector size, and the default in WebPAM PROe.

P

referred

c

OntrOller

id

When you create a logical drive using the Advanced method of disk array creation, you can specify the Preferred

Controller ID: