How to understand RAID disk striping size?
Posted on 2010-09-19
I am reading article talking about RAID disk drive striping, below are statement about the sizing:
During intense I/O operations, performance can be optimized by striping the drives in the array with stripes large enough so that each record potentially falls entirely within one stripe segment. This helps insure that data and I/O operations are evenly distributed across the arrayed drives, thus allowing each drive to work on separate I/O operations at the same time.
By contrast, in data-intensive applications that access large records, smaller stripe sizes can be used so that each record will span across many, or all, of the drives in an array with each drive storing only part of a record’s data. This allows long record accesses to be performed faster, since the data transfers can occur in parallel on multiple drives in the array. Applications such as digital video editing, audio/video on demand, imaging and data acquisition that employ long record accesses are examples of applications that often achieve optimum performance with smaller stripe sizes.
Unfortunately, smaller stripe sizes typically rule out multiple overlapping I/O operations since each I/O will typically involve all of the drives.
I am not quite understand the differences of configuring smaller striping size and larger striping size. after the reading, I get a feeling that smaller striping size is, it can be more easily to span across multiple disks, therefore, more efficient in I/O operation??