What is a Hybrid Storage Array?

RAID, Inc. is offering answers to our most frequently asked questions via our blog.  We will compile them into an FAQ page soon.  Here’s the latest!

What IS a Hybrid Storage Array?

The simple definition of what a Hybrid array is is the use of SSDs with spinning disks in one array. RAID, Inc. goes far beyond that simplified definition, however.  Our tiering technology overcomes the two major limitations found in most tiered or Hybrid storage systems today by (1) automating the migration of data in (2) real-time.

The system virtualizes both the SSDs and HDDs at the sub-LUN level using 4 MB pages distributed across multiple RAID sets. Intelligent algorithms then continuously monitor I/O access patterns and automatically move Hot Data to the SSDs to maximize I/O operations and, therefore, improve performance of the aggregate application workload.

This Intelligent I/O Algorithm Utilizes Three Separate Processes in Real Time:

1. Scoring

Scoring to maintain a current page ranking on each and every I/O using an efficient process that adds less than one microsecond of overhead. The algorithm takes into account both the frequency and recency of access. For example, a page that has been accessed 5 times in the last 100 seconds would get a high score.

2. Scanning

Scanning for all high-scoring pages occurs every 5 seconds, utilizing less than 1.0% of the system’s CPU. Those pages with the highest scores then become candidates for promotion to the higher-performing SSD tier.

3. Sorting

Sorting is the process that actually moves or migrates the pages: high scoring pages from HDD to SSD; low scoring pages from SDD back to HDD. Less than 80 MB of data are moved during any 5 second sort to have minimal impact on overall system performance.

RAID, Inc. offers the ARI-100 Series as an optimal solution for hybrid storage.  Contact us to learn more about this flexible, scalable option.