Power Systems Refreshes Flash Drives, Promises NVM-Express For IBM i
April 29, 2019 Timothy Prickett Morgan
There was a time after Mark Olsen retired a few years back when the presentations concerning Power Systems hardware as it related to the IBM i platform were not as detailed as we were used to. But a new team of people are running the show now, and they are getting better and that helps us all understand what Big Blue is doing on the hardware front even better.
As part of the April 23 announcements, IBM added a bunch of new storage and networking peripherals to its Power8 and Power9 system lineup. You can read all about it in detail in announcement letter 119-001, which covers the AIX, Linux, and IBM i angles, but we have found a table that better encapsulates the information specifically for IBM i platforms, which is presented here and which also shows what releases of IBM i provide support for this new hardware:
Let’s go through this. First of all, IBM has qualified a new generation of mainstream SAS 2.5-inch flash drives (with 4K blocks) for Power8 and Power9 systems that come in 931 GB, 1.86 TB, 3.72 TB, and 7.45 TB capacities. To use that fattest flash drive, you need to jack up the LUNs on the storage and it only works on IBM i 7.4. The 931 GB SSD costs $2,225, or $2.39 per GB, while the 1.86 TB drive costs $3,999 or $2.15 per GB. The 3.72 TB drive offers the best bang for the buck of the four new SSDs, at $6,799 or $1.83 per GB, and the 7.45 TB unit costs $14,999 or $2.01 per GB. It is interesting to compare these mainstream SAS SSDs to the enterprise grade ones, which are a lot less capacious but can take a heavier beating. The new 387 GB enterprise-class SSD costs $2,175 or $2,375, depending on the Power Systems model, which works out to $5.60 to $6.14 per GB. The new 775 GB enterprise SSD costs either $3,175 or $3,375, which works out to $4.10 to $4.35 per GB. And the 1.55 TB enterprise SSD costs $5,975, or $3.85 per GB. Clearly, that enterprise grade comes at a premium, which is better for a heavier mix of writes, which wear out flash and therefore requires them to have more latent flash memory embedded in the device to hold data as the flash burns its little bit holders.
As in the past, IBM warns that the mainstream drives are not made for heavy write environments, and says that the mainstream SSDs have the following Total Bytes Written (TBW) ratings for the lifetime of these SSDs:
- 931 GB unit, 1,700 TB
- 1.86 TB unit, 3,399 TB
- 3.72 TB unit, 6,799 TB
- 7.45 TB unit, 13,601 TB
IBM is also adding support in Power9 iron for various legacy I/O devices, as follows:
- PCI-Express 3.0 3D Graphics Adapter x16 (#EC51) for Power L922, S922, and H922 servers
- PCI-Express 3.0 2-Port 40 GbE NIC RoCE QSFP+ Adapter (#EC3B) for Power E980 and E950 servers
- PCI-Express 3.0 LP 2-Port 40 GbE NIC RoCE QSFP+ Adapter (#EC3A) for Power E980 server
- PCI-Express 3.0 LP 2-port 100 Gb EDR IB Adapter x16 (#EC3E) for Power E980 server
- PCI-Express 3.0 LP 1-port 100 Gb EDR IB Adapter x16 (#EC3T) for Power E980 server
- PCI-Express 4.0 LP 2-port 100 Gb EDR IB CAPI adapter (#EC64) for Power E980 server
- PCI-Express 4.0 LP 1-port 100 Gb EDR IB CAPI adapter (#EC62) for Power E980 server
- PCI-Express 1.0 SAS Tape/DVD Dual-port 3 Gb x8 Adapter (#EJ1N, #EJ1P) for Power E980 server
- Expanded function Storage Backplane 8 SFF-3 Bays/Single IOA with Write Cache (#EJ1G) with AIX® operating system support for Power S922 and H922 servers
- Specify Mode features with SAS Controller (#EJ0L) for EXP12SX/Power EXP24SX for Power E950 server, supported for migration only
- 387 GB (#ES0Q) and 775 GB (#ES0S) SFF-2 4K SAS SSDs for Power E950 server, supported for migration, but not as a new order
- 1.2 TB 10K RPM SAS SFF-2 Disk Drive (#ESD3) for Power E950 server, supported for migration, but not as a new order
- 600 GB 15K RPM SAS SFF-2 Disk Drive – 5XX Block (#ESDP) for Power E950 server, supported for migration, but not as a new order
In the same announcement, IBM says that it will support PCI-Express 3.0 flash drive with low latency NVM-Express ports across the Power9 scale out and scale up lines, and that these will be available in 1.6 TB, 3.2 TB, and 6.4 TB capacities. NVM-Express flash drives have a much more streamlined and flash specific protocol that does not in any way make use of the SCSI driver in the AIX, Linux, or IBM i operating systems and therefore radically lowers the time it takes to read and write data to the same flash devices. The 1.6 TB NVM-Express drive costs $3,099, or $1.94 per GB, while the 3.2 TB unit costs $6,099 or $1.91 per GB and the 6.4 TB unit costs $12,099 or 1.89 per GB.
While AIX and Linux can utilize these NVM-Express SSDs, neither direct configuration by IBM i or through the Virtual I/O Server (VIOS) is supported with the IBM i platform at this time. But IBM did have this to say about it in a statement of direction buried in the April 23 announcements: “IBM plans to add native support for Non-Volatile Memory Express (NVM-Express) devices in the IBM i operating system.” When that will happen remains to be seen. But probably sooner rather than later.