For those who don’t know me yet, my name is Richie Palma and I work for an IBM BP in Grand Rapids Michigan. I’m most likely 15 to 20 years younger than the average IBM i enthusiast, which puts me in a fairly unique position. I’m blessed to work with customers that are using both IBM Power systems and IBM i the way it’s meant to be used.
In this post I am going to share my three favorite IBM Power System configurations for mid-sized businesses running IBM i. I will touch on each configuration from a high level vantage point and hit some of the benefits as well as the drawbacks of each. As you read on, you may notice that I focus a considerable amount on disk as I touch on each option. Memory and core licensing are affected considerable by the needs of the organization. With that being said, based on my understanding of the marginal cost difference between 32gb and 128gb of memory, I would have to be talked out of the 128gb. So moving forward let’s just pretend each one of these configurations is running 128gb.
Configuration 1 – Keep it simple; leave everything in the Power8 backplane.
By far, one of the best things that IBM Power8 delivers is the large 18 drive backplane. When I first learned about the larger backplane in the Power8 announcement it didn’t fully register in my mind what kind of impact this would have on my customers that didn’t have huge disk requirements. With the Power7+ backplane having only 8 drives, if a customer needed additional disk for either capacity or arms, we needed to move them into an expansion drawer.
You can read more about the benefits of the Power8, 18 drive backplane in my previous article titled “Benefit for Mid-Sized Business’s running on IBM Power8 (S814 & S824) Systems”.
To maximize disk arms for performance, we typically fill the system unit up with 15k RPM SFF drives that are offered in either 139gb, 283gb, or 571gb capacity. As you would imagine, the bigger the drive the bigger the price tag so understanding the projected growth of the business is important in deciding which drives we will choose.
- 18x 139gb 15k RPM SFF drives (-2 drives for RAID & Hot Spare) = 2.2TB usable
- 18x 283gb 15k RPM SFF drives (-2 drives for RAID & Hot Spare) = 4.5TB usable
- 18x 571gb 15k RPM SFF drives (-2 drives for RAID & Hot Spare) = 9.1TB usable
We have yet to configure a system with 571gb drives because most customers that need that much overall disk capacity also need to spread the disk i/o across more drives then just the 18 drives in the backplane. This is a good point to transition into my next Power8 Configuration.
Configuration 2 – We love the 18 drive backplane, but need a little more i/o from our disk.
In an effort to limit the duplication of information I will leave the intro to “The Power8, 18 drive backplane is really cool”. That’s why I’m going to use it in the second configuration as well. In Power7+, the RAID card supported in the system unit wasn’t anything to be proud of so if you needed a decent chunk of disk then you would be better off running all the drives through the RAID card dedicated to the expansion drawer.
With Power8, the integrated raid card in the system unit offers great performance, allowing you to take advantage of the systems drive bays in addition to adding an expansion drawer.
For mid-sized customers we like the 5887 drawer which offers an additional 24 SFF drive bays in a 2U rack mount drawer. The 5887 expansion drawer offers hot-swap, redundant AC power, and is connected to the Power8 through redundant SAS cables. As with the first configuration, we are a big supporter of not leaving yourself disk constrained. Just because you could pack your data onto 18 of the 571gb drives and have room for growth doesn’t mean that your system is going to like writing all that data across only 18 drives.
- 42x 139gb (18 in Server + 24 in Expansion) 15k RPM SFF drives (-5 drives for RAID & Hot Spare) = 5.1TB usable
- 42x 283gb (18 in Server + 24 in Expansion) 15k RPM SFF drives (-5 drives for RAID & Hot Spare) = 10.4TB usable
- 42x 571gb (18 in Server + 24 in Expansion) 15k RPM SFF drives (-5 drives for RAID & Hot Spare) = 21.1TB usable
Configuration 3 – Lets take storage to the next level and move to an IBM Storwize SAN and VIOS host.
I’m going to break this one up into a few sub configurations due to the many options IBM’s V3700 SAN brings to the table. One major difference in this configuration is the use of VIOS as the host partition.
VIOS is part of all PowerVM editions. It is a special-purpose partition that allows the sharing of physical resources between logical partitions in order to allow more efficient usage of physical system resources. VIOS allows client partitions to share access to resources, minimizing the number of physical adapters needed in to support multiple LPAR’s. The VIOS eliminates the requirement that every partition owns a dedicated network adapter, disk adapter, and disk drive.
Sharing these resources allows us to allocate processor, disk, and memory to logical partitions at a virtual level. If you have worked with us in the past you have probably heard us reference “slicing and dicing disk, memory, and processor” across partitions. VIOS is how it’s done.
Easy Tier on V3700 SAN
Giving I/O some rocket fuel with a few SSD’s and “Easy Tier” has huge benefits for company’s willing to spend the extra cash on SSD’s. Easy Tier automates the placement of data among different storage tiers and boosts infrastructure performance to achieve optimal performance through software, server, and storage solutions. The idea is to find and store the high traffic data on the SSD’s and utilize HDD’s to handle the slower moving information.
Disk i/o is something I have become intimate with through many conversations with Larry Bolhuis. Larry is one of the best mentors a new member of the IBM Power Systems space could have. If you ever get a chance to hear Larry Bolhuis speak please, make sure you take advantage of it. Many of the groups our team works with come to us because of system performance issues. The first thing most of them want to do is throw more memory at the box or turn on another core to add some extra horse power. While those options will give you some added horse power, they won’t do much if your current system is disk constrained. There is a limit to how many reads and writes a single drive can produce in a given amount of time. So if you don’t have enough disk arms to handle the read/write needs of your business, then you experience delays. If you add additional lanes for the traffic to flow, you remove that constraint. But additional lanes (additional drives) can become pricey and hard to cost justify when you have more than enough overall storage space.
With the V3700 SAN and Easy Tier your able to greatly reduce the disk i/o limitations of traditional spinning disk. This significantly reduces the fear of not having enough i/o to support the read/write demands of the business and opens up many possibilities for mid-sized businesses who run high transaction workloads.
Another great benefit to the V3700 SAN configuration is its ability to share storage with other infrastructure within your data-center. The last few years have brought on a big push to shrink the datacenter footprint through virtualization as well as sharing resources. For many years the thought of a mid-size business connecting a SAN to an IBM Power System running IBM i was not practical due to costs. Today we are writing a much different story with the V3700 carrying a very comparable price to IBM i specific disk.
Wrapping up the V3700 option
This is a great solution for companies who are ready to embrace what many IBM i shops would consider “out if the box” thinking. The ability to monitor and manage storage at the SAN level from a dedicated GUI interface is a great addition to the traditional storage management for IBM i system administrators. The look and feel of the SAN based GUI interface ads a level of comfort, desired by the next generation of systems administrators. You may also be interested in the video “The features and benefits of Storwize V3700 entry storage system”
These are all great configurations for mid-size companies that are embracing the performance, reliability, and scalability of IBM Power8 technology. With that being said, these are very high level hardware configurations and as we know the devil is in the detail. It is important that your business partner does a thorough review of both your hardware and software requirements prior to moving forward with an upgrade. If you want more information check out some of these other great posts.
Power8 Comparison – S814 vs. Power7+ 720
9 Great Documents for Getting to know IBM Power8 Technology
IBM i Power Systems External Storage Support Matrix
Benefit for Mid-Sized Business’s Running on IBM Power8 (S814 & S824) Systems
Enabling success on the POWER8 platform
If you have any questions or are in need of an IBM business partner to walk through the upgrade journey with, send me an email. I would be glad to help in any way I can.
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