Magazine Article | November 1, 2001

More Storage Than Meets The Eye

Source: Field Technologies Magazine

By optimizing your current storage utilization, storage management software can increase your applications' performance and reduce your hardware expenditures.

Integrated Solutions, November 2001

While there may be the rare person who is observant without fail, most people can recall noticing, for the first time, something they could have - no, should have - seen long ago. You're driving home down the same street, past the same houses - just as you have day after day after day. Suddenly, the familiar becomes unfamiliar, and you wonder, "When did the Jacksons paint their house gray?" "Oh, only about five years ago!" says your stunned passenger.

For larger companies, storage infrastructure can be like that. First, the network neighborhood grows - more servers, more applications, more users, more storage devices, and more disk arrays. Suddenly, desktop users and/or IT staff start noticing system performance problems but can't recall a specific moment of change that triggered them. They may be tempted to buy more storage as a way of alleviating the problems. Behind the symptoms, however, may be a storage utilization problem - perhaps even excess capacity not currently in use. Consequently, in order to focus on the real causes of slowdowns, companies may want to rely on the vision of storage management software.

Take Software On The Storage Treasure Hunt
Whether or not companies are currently experiencing sluggish system performance, storage management software can be a solid investment, particularly during periods of financial belt-tightening. Companies have traditionally addressed storage expansion needs by throwing more money - i.e. more hardware - at the problem. But they may not be able to continue to afford that approach. Furthermore, with storage management software's capabilities for optimizing current storage resources, customers may not always need to buy more equipment, even if they can afford it.

Chris Gahagan, VP and general manager of recovery and storage management for BMC Software, Inc. (Houston), points out that unit prices for storage devices are dropping, but overall storage expenditures are not. "There's a fallacy that, just because storage hardware is becoming cheaper, enterprise storage is becoming cheaper. It's actually not becoming cheaper because the amount of data that companies are saving is growing," Gahagan said. "As a percentage of an IT budget, storage is becoming larger and larger. Our enterprise customers allot 45% to 60% of their IT spending to acquiring storage gear."

Augie Gonzalez, director of product marketing for DataCore Software Corp. (Ft. Lauderdale, FL), notes that the current economic slowdown has forced companies to reassess how they tackle storage needs. "Whereas previously they may have considered buying additional disk arrays, now they're trying to kick up the utilization of the disk space they already have. By using software to help pool their existing storage resources, companies can often double or even triple their storage utilization," Gonzalez said.

Reallocate Current Storage Resources
According to Gahagan, companies don't always think "storage problem" when their applications seem to be performing slowly. Database applications, in particular, offer a representative example because they rely heavily on the performance of underlying storage arrays. Users often assume that, if a database application is running slowly, they need some database tools to increase its performance. However, the problem might lie in how their storage is provisioned. "Since our software is constantly getting statistics on storage array performance, we know the average latency for I/O (input/output) transactions. If latency gets abnormally long during a database query, for instance, we can look at the logical storage units representing the database files and tables," Gahagan explained. "We've found that, in most databases, only a few tables are active. Even if they are active, most of the activity is read activity, not write activity. But we'll find customers storing that data to a RAID (redundant array of independent disks) 1 array, which may be overkill if they're not doing much write activity. We might suggest taking the load off of the RAID 1 array by moving the logical units associated with particular database tables to a RAID 5 array. RAID 5 is a good choice if you don't need to do a lot of writing. Plus, because RAID 1 uses pure mirroring, it requires twice as much storage as RAID 5." (For an explanation of the various RAID levels, see "RAID - What's It Mean To You?")

Reduce Planned Downtime
Gonzalez agrees that poor storage infrastructure design can lead to downtime. However, he believes most companies have taken precautions to minimize unplanned downtime. But, he sees storage management software as a solution to a different kind of operational intrusion - planned downtime. "Companies often have excess storage capacity behind some servers, while other servers are starving for space. That's the predicament they find themselves in," Gonzalez said. "Systems administrators may be conditioned to think they'll have to shut down machines in order to add or move capacity or to redirect I/O operations. They think it's natural to schedule downtime." According to Gonzalez, storage management software can allow administrative functions to be performed behind the scenes during normal working hours. "Storage management tools can offer network users a virtualized storage environment. Because applications are insulated from the storage management chaos, they can be served without disruption. With sustained uptime, companies can get more duty cycles out of their existing servers."

In offering basic advice about alleviating storage pain, Gahagan encourages companies to avoid trying to target all symptoms in the initial treatment. "We tell our customers to prioritize and solve storage problems one at a time," Gahagan said. "Once you solve the first big problem, your approach to the second problem will be different because you've already changed your operational procedures." Finally, Gahagan asserts that storage reallocation should be driven primarily by the needs of desktop application users. "Managing storage because it's storage merely solves a storage problem. But, managing storage around applications can start to solve business problems," Gahagan said.

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