Many hardware vendors are on the verge or have already released their new certified SAP HANA servers based on the Intel Ivy Bridge v2 CPU and related chip sets. So what does this actually mean to the consumer?
- A faster RAM chip means faster query response time. The Ivy Bridge v2 CPU support DIMMS based on the DDR3-1066, 1333 or 1600 MHz architecture. The previous generation of servers only supported DDR3 memory clock speeds of 800, 978, 1066, 1333 or 1066. Faster clock speeds mean faster seek times. The net result is a faster SAP HANA system.
- A faster CPU clock also means faster query response times. The certified SAP HANA systems running the Ivy Bridge v2 CPU support clock speeds of 2.8 GHz with turbo speeds of 3.4 GHz. The previous generation of E7 CPU operated at 2.4 GHz with turbo speeds of 2.8 GHz. A faster clock means fewer wait cycles and a faster SAP HANA system.
- The Ivy Bridge v2 CPU supports 15 cores per CPU socket. This allows SAP HANA to perform more parallel calculations which results in faster speeds and greater workloads. There are more benefits as well:
- This allows hardware vendors to supply customers with a 4 sockets (60 core) server that supports 1TB of RAM. Unless something recently changed, SAP has always maintained that the ratio between RAM and CPU core needs to be around 16GB per Core for analytical solutions. The previous generation of 10 core CPUs could only achieve his with an 8 socket motherboard. Because Ivy Bridge V2 supports 15 cores per socket, vendors can now operate 4 socket SAP HANA systems that host 1 TB of RAM. In general this will help reduce the cost of the 1TB server. 8 socket chassis and motherboards are generally very expensive. A 4 socket alternative will likely be less expensive.
- For S0H (Suite on SAP HANA) the ratio is different. In general 32GB per core is supported. This means that a 4 socket (60 core) server can now host 2TB of RAM. This will also greatly reduce the cost of SAP HANA systems operating SoH.
- SAP claims that the overall benchmark yields a 2x increase in speed compared to the 1st generation of certified SAP HANA systems. However, I still think we need verify the performance as vendors try to support 1TB of RAM on the 4 socket architecture. If you think about it, the 1st generation 8 socket systems supported 80 cores. The new 4 socket Ivy Bridge v2 systems support 60 cores. Their is a CPU/RAM ratio difference of 80/60 to 12.8GB/17.1GB (1024 GB / 60 or 80). Perhaps the faster memory clock speeds and other enhancements to Ivy Bridge v2 easily overcome any issues? I guess we will need to wait until official benchmarks are available before passing judgement.
- Some vendors are able to build XS (Extra Small) through XL (Extra Large) SAP HANA systems on the same server chassis and motherboard platform. This will allow organizations to scale up or add RAM and CPU’s as needed. The previous generation of servers were based on a variety of platforms. Often organizations would have to purchase a new server when they needed to scale up.
- The logging partition appears to no longer require super fast PCIx Nand Flash cards? The first generation of SAP HANA servers were all equipped with Fusion IO cards or RAID 10 SSD arrays. The 2nd generation appears to have relaxed the IOPS requirements. If this is truly the case, the storage cost for SAP HANA servers should also be greatly reduced. The PCIx cards and SSD arrays are very expensive. If SAP HANA can operate its logging mechanism at optimal speeds, on a partition using more cost effective spinning disks, you should expect a less costly SAP HANA server.
- Note: SAP HANA stores and accesses date in RAM. The disks only contain redundant information in case of a power failure. The only conceivable downside to a slower logging partition, is a scenario where bulk loading large chunks of data to SAP HANA is slowed. It can also affect the SAP HANA startup time. When started, SAP HANA takes ROW data from disk and lazy loads COLUMNAR data as needed. If the anything needs to be recreated from the logs at startup, I would assume that a faster disk is better. The new question is, “how much better”?
- Note: I have an open question to SAP on why the logging partition no longer requires fast disks. Something must have changed?
SAP Certified Appliance Hardware for SAP HANA: http://scn.sap.com/docs/DOC-52522
SAP Certified Enterprise Storage Hardware for SAP HANA: http://scn.sap.com/docs/DOC-48516