It’s now mid-March, and with that comes the annual NCAA American college basketball tournaments for men and women, AKA “March Madness”. To be perfectly honest with you, I really don’t care about March Madness. I’m a hockey guy, and this time of year, with the NHL Stanley Cup playoffs (my favorite time of year) just around the corner, I have hat tricks on the mind. For those of you unfamiliar with the term, a hat trick is when a player scores three goals in a game. That brings me around to the real subject of this blog post: IBM scoring a “mid-range” hat trick with the new z13s, DS8884, all connected with the IBM SAN48B-5 FICON switch.
IBM announced the z13s on 16 February 2016. The z13s delivers the industry leading performance, reliability, availability, and security that the IBM z13 has, in a smaller package intended for small to midsize companies. Compared to the zBC12, the z13s offers 34% improvement in single thread capacity, 8x the memory (up to 4TB) and up to 43% improvement in total capacity. z13s also offers the same impressive I/O features and functions of z13 such as FICON Express 16S channels.
The z13 is an impressive computing platform; however, for many customers, even some large enterprise customers, it is too powerful of a machine. Like the largest enterprise z Systems clients, these businesses want to have the latest technology for mobile, analytics, and cloud computing to enable what IBM terms a cognitive business. The z13s is a perfect fit for these customers looking to get the security, and hybrid cloud capabilities of z Systems, at the right size (and cost) for their business.
Fact: 92 of the largest 100 global banks run their business on IBM z Systems. Today, a majority of these top 100 banks, including the majority of the top 20 world banks, use IBM DS8000 series DASD in combination with z Systems for their core banking applications. In October 2015, IBM announced the DS8880 models of DASD arrays. Similar to the “Business class” vs. “Enterprise Class” distinctions of the prior model DS8870 and the IBM mainframes, IBM announced two new models, the DS8884 and DS8886. The DS8884 is the “Business Class” variant and as such makes an ideal partner for the z13s. IBM Fellow Harry Yudenfriend wrote a great blog on the reasons the z13s and the DS8884 are a perfect match. I’ll summarize briefly: “The DS8884 complements the z13s by providing a more cost effective entry point for mainframe storage, new and enhanced resiliency features, full architecture compatibility with the full DS8000 family of storage systems, performance optimizations for mainframe and distributed workloads and simplified licensing for advanced functions.”
The DS8884 has 6-core controllers, up to 256 GB cache, 64 FICON Express 16S channels, up to 240 drives in a single 19 inch (40U) rack or 768 drives in a three frame configuration, and up to 120 flash cards in High Performance Flash Enclosures (HPFEs). IBM has documented performance that is equal or better than existing DS8870 systems. Some highlights centered on I/O:
Faster analytics with up to 32% reduction in batch elapsed times for I/O bound jobs for improved application and middleware I/O performance with FICON Express16S channels.
Performance measurements show a 7% reduction in write I/O service time (512K writes) at data center distances and up to 68% reduction in I/O service times at 100km.
Accelerated transactions by reducing DB2 commit times by 66% when writing data remotely with DS8880 zHyperWrite and z13s FICON Express16S channels.
Significant reduction in bit error rate (improved performance and reliability) of up to 300x. The z13s FICON Express16S channels and the 16Gbps host adapter in the DS8884 both support Forward Error correction (FEC) technology. This bit error rate improvement is the equivalent to doubling the optical signal strength.
The IBM System Storage® SAN48B-5 (aka Brocade 6510) switch is designed to meet the demands of hyper- scale private or hybrid cloud storage environments by delivering Gen 5 Fibre Channel technology and capabilities with 16 Gbps performance that support highly virtualized environments. To enable greater flexibility and investment protection, SAN48B-5 is configurable in 24, 36 or 48 ports and supports 2, 4, 8, 10 or 16 Gbps speeds in an efficiently designed 1U package. The recently enhanced SAN48B-5 is fully qualified for IBM z Systems and FICON environments, including z13 and z13s. As can be seen by the various z Systems switching qualification letters on IBM ResourceLink, the SAN48B-5 (Brocade 6510) is the only non-director class switch (smaller switch) qualified by IBM zSystems for z13 and z13s. Cisco does not have a similarly qualified switch.
Why switched FICON/zHPF for a z13s-DS8884 environment?
Many z13s/DS8884 end users may be thinking that with a smaller number of FICON Express16S channels and 16Gbps host adapters on the DS8884, they do not need a FICON director and should go the direct attached route for their FICON/zHPF connectivity. It likely is true that these clients will not require the number of ports a FICON director provides and/or will not be able to justify the cost of FICON directors, even a four slot model such as the IBM SAN384B-2. However, there are significant technical and business benefits to running switched FICON/zHPF. A newly published IBM technical white paper (Why Switched High Performance FICON for z Systems?) that Brocade and IBM collaborated on covers these technical and business benefits in great detail. Let’s summarize:
Consolidation: switched architectures use fewer channels, fewer host adapter ports on storage devices, and allow for the end user to run these at higher utilization rates.
Higher availability - Most z Systems end users plan 8 paths to a device. Unlike a direct attached architecture, using a switched architecture allows you to still have 8 paths to a device, even when there is a failure.
Use Fan-In/Fan-Out architectures - Switched architectures allow the end user to use fan-in/fan-out designs to have fewer, higher utilization (expensive) channels connected to more lower utilized host adapter ports on storage devices.
Scalability – It is more likely for large configurations with a z13s to run out of FICON channels when using direct attach architectures
Distance - FICON channels will support up to 10 km distance without a switch. For longer distances, a switch is required due to buffer credit issues.
Linux and NPIV - Customers running large Linux on z implementations will want to use Node Port ID Virtualization (NPIV) to consolidate the number of FCP channels being used. NPIV requires a switched architecture.
For z13s/DS8884 end users, the IBM SAN48B-5 is the ideal platform (and the only z Systems qualified switch) to provide these benefits. It uses the same ASICs as the FICON director class products, so it has the same technology features and performance capabilities as FICON director class products. The SAN48B-5 uses Brocade Fabric Vision technology to simplify the management and monitoring of the FICON SAN. Lastly the SAN48B-5, like the z13s FICON Express16S channels and the DS8884 16Gbps host adapters, supports FEC. A z13S-SAN48B-5-DS8884 configuration provides high performance, high availability 16Gbps FICON links with FEC end to end.
Brocade FICON switching technology provides the FICON SAN infrastructure for all 20 of the top 20 largest banks in the world I mentioned earlier. There are significant benefits to using switching for all FICON environments, including “mid-range” environments with the IBM SAN 48B-5 connecting z13s and DS8884. The combination of z13s, DS8884, and IBM SAN48B-5 is 3 scores for the end user who implements them together: in other words, the z13S-DS8884-SAN 48B-5 is a “mid-range” hat trick. The team with a hat trick usually wins.
I hope you enjoyed the blog. Please let me know what you think (about this post, or this year’s Stanley Cup Playoffs).