Supercharging Applications Through Data Path Optimization

What if you could optimize your data paths to get the most out of your storage investment? 

You’d do it, unless you had money to burn. You’ve got a lot invested in hardware and software and an angry mob—er, users—at your door.

In the 1985 movie Back to the Future, Doc Brown created the Flux Capacitor to kick his DeLorean automobile into another time period.

No amount of fossil fuel was going to get him and his ride to his destination.

Similarly, with today’s sophisticated data centers, no amount of hardware or manual intervention is going to tune the data path connections between servers and storage to provide the performance, availability, and scaling you need.

You need a path management solution that will put your data paths into overdrive.

The Reality of the Situation

As a data center manager, or storage, server, or virtualization administrator, you need to deliver consistent application performance and data availability to your organization. While cost reductions have been a top priority in IT spend decisions in recent years, business process improvement is gaining in importance. Keeping mission-critical applications online and optimal enables greater productivity.

But, it’s not easy.

Many operating systems include some form of data path management for providing simple failover and for some assurance of application availability during the normal course of business.

However, these path management solutions don’t eliminate I/O bottlenecks, don’t deliver performance, and don’t scale.

Plus, they are particular to one operating system and do not span multi-vendor environments, and vary in the tools they provide.

Data Path Management for Availability and Performance

For some time, EMC has had a data path management solution called PowerPath. This server-based software goes out the door with most of the arrays and does a bang up job providing high availability and contributing to the overall performance of the storage environment.

EMC PowerPath provides automated data path management, automated failover and recovery, optimized load balancing and non-disruptive load-based bus and path testing.

It supports multiple operating systems including Windows, Linux, vSphere, AIX, Hyper-V, HP-UX, and Solaris. Though from an array vendor, it is not proprietary and supports EMC as well as qualified non-EMC storage arrays.

Recently, the Enterprise Strategy Group (ESG) tested PowerPath for Windows performance against Windows native MPIO.

PowerPath uses patented algorithms that determine and use the best data paths available. Windows MPIO defaults to a round robin distribution that comparatively speaking provides minimal benefit to customers when it comes to data path health and viability.

The results were impressive!

PowerPath provided consistently faster performance than Windows MPIO in every test.

The ESG Lab testing was designed to track how PowerPath and MPIO respond to changes. The primary Windows hosts ran various ESG I/O profiles created using the Iometer workload generation utility.

Some I/O profiles focused on I/O per second (IOPS) to simulate Exchange data, OLTP, and file-serving workloads. Other profiles emulated throughput-intensive workloads to simulate backup, video-on-demand, decision support, and Exchange log traffic.

Let’s take a look at the results in each of these areas.

As we do, please keep in mind that these tests were designed to simulate the real-world SAN conditions that organizations encounter every day.  The tests were conducted using common tools to highlight the potential impact on application, SAN, and storage performance.

While these test results represent what a user might experience, actual results will vary depending on the data center configuration.  In other words, YMMV (your mileage might vary).

IOPS-Intensive Workloads

In these tests, ESG Lab generated file serving, Exchange database, and 8K OLTP workloads on one server configured for PowerPath and another configured for Windows. Simultaneously, five other Windows servers generated backup reading workloads to create resource contention.

Windows MPIO retained its round robin distribution and continued to place I/O on the clogged data path.

PowerPath, on the other hand, determined that the jammed path was not optimal and automatically redirected I/O traffic to better paths.

Since intelligently applying the workload over the data paths, PowerPath performed better handling 22% more IOPS for OLTP, 31% more IOPS for Exchange, and 33% more IOPS for file serving than Windows MPIO.

Throughput-Intensive Workloads

Next, ESG Lab generated another set of tests; this time with decision-support, Exchange-log, and video-on-demand workloads on one server configured for PowerPath and another configured for Windows. Simultaneously, five other Windows servers generated backup reading workloads to create resource contention.

These throughput-intensive tests simulated what happens when a heavy download workload is place on the environment, potentially dragging all application performance down.

In this scenario, PowerPath not only fared better, it excelled!

PowerPath was 105% faster for decision-support, 148% faster for Exchange logs, and 203% faster for video-on-demand than Windows MPIO.

The Importance of It All

The many demands on your server, network, and storage resources can lead to service-level delivery issues. Oversubscribed ports, faulty HBAs, bad cables, and flaky data paths can easily result in business-process performance degradation.

Don’t trust your ability to deliver on service levels—and potentially your job—to  a generic data path solution that does not have the intelligence to automatically adapt on the fly to the changing elements and shifting workloads in your data center.

Round robin MPIO policies go ‘around in circles’.  They do little, if anything, in the area of data path health and viability.

PowerPath intelligently manages data paths selecting the best available path based on availability and ability to handle required workloads. By combining automated data path failover and recovery with optimized load balancing of changing workloads across all available data paths, PowerPath delivers both high availability and a performance boost to your applications.

Back to the Future—and What It Means to You

Well, the great results don’t end there; PowerPath use the same patented algorithms or secret sauce in each version for each supported operating system. This means that regardless of the flavor, similar performance benefits should be realized in other PowerPath-supported operating system environments not just Windows.  

Imagine one data path management solution for physical and virtual environments—remember vSphere and Hyper-V are supported.  This sameness provides standardization on top of the data path automation and optimization afforded by PowerPath.

You can use PowerPath to maximize application performance and availability across your data center, while reducing the cost of maintenance and staff.

But, don’t just take my word for it, read the ESG Lab: EMC PowerPath vs. Windows Native MPIO yourself.

About the Author: Mark Prahl