Investigate a variety of innovative Solid-State Drive solutions
Looking at just the internal or DAS solutions, PCIe-based and SAS-bay-based SSD solutions have few, but important differences. Although these two solutions have different configuration characteristic and prerequisites, a paramount commonality exists between these two solutions: great performance.
The SAS-bay-based SSD option is perhaps the most versatile option available today. Leveraging the same SAS bays which HDD use, this option also uses the higher performance SAS controllers. It’s a great option! These SAS bays can contain one or more 177 GB or 387 GB SSDs (one per bay), which are then connected to a PCI SAS controller.
- Is compatible with both POWER6 and POWER7 servers including the POWER7 PS703/PS704 blades and Flex Systems. (177 GB SSD for POWER6 servers, 177 and 387 GB for POWER7 servers)
- Is supported by AIX 5.3 and later, IBM i 6.1 and later, as well as Linux (REHL and SLES).
- 387 GB SSD and 177 GB SSD available in either SFF-1 or SFF--2 SAS hot-swap bays (SFF = 2.5-inch bays).
- Is supported by either PCIe or PCI-X SAS adapters with write cache for an additional performance boost.
- Uses enterprise-quality, high performance eMLC Flash technologies.
- Can support more SSD per PCI slot or per SAS controller than a PCIe-based option.
A specialized, ultra-dense, ultra-performance SAS-bay SSD option was introduced in 2012., The EXP30 Ultra SSD I/O Drawer. Its SAS hot-swap bays are designed only for 1.8" 387 GB SSD and do not support HDD. The Ultra SSD Drawer can provide up to thirty1.8” 387 GB SSD in a 1U drawer with integrated SAS controllers which attaches into the Power System without a PCIe slot. This is amazing world class technology which is supported on most of the POWER7 servers and all of the POWER7+ servers.
The PCIe-based SSD option is based on a double-wide PCIe adapter. Differing from the SAS-bay-based option, 177 GB SSD modules plug directly onto the adapter. In turn, this eliminates the need for SAS bays and cabling, but also limits the maximum number of SSD modules to four per PCIe adapter.
Depending upon the configurations being compared to the current 177 GB SAS-bay-based SSD offering, the new PCIe-based SSD offering’s 177 GB capacity can offer a per-GB capacity price savings and a smaller per-GB footprint or the SAS-bay based option may offer a price savings.
- Is supported on most POWER7/POWER7+ servers, but not on the Power 795.
- Is supported by AIX 5.3 and later, IBM i 6.1 and later, and Linux.
- Uses enterprise-class eMLC Flash technology to provide larger capacity, better price-performing SSD modules.
- Contains SSD modules that require the PCIe adapter to be removed from the PCI slot before they are replaced. (You can mirror the modules across two or more PCIe adapters when hot-swap capability is important.)
- Can provide a very cost effective solution when you just need a few SSD compared to a SAS-bay-based option.
Enterprise MLC Technology
eMLC technology stands for "Enterprise Multi-Level Cell" Flash memory technology. IBM was the first server vendor to provide this new SSD technology option which blends enterprise class performance and reliability characteristics with the more cost effective characteristics of MLC Flash storage.
Using advances in both the SSD device controller Flash memory management plus advances in MLC technology itself, IBM can now provide much better cost on a per GB basis, much more dense physical packaging and about 50% less energy consumption and heat per drive.
More impressively, eMLC does this while continuing to provide great sustained performance levels and extended endurance/reliability. For example, the new IBM eMLC SSD modules were designed to provide 24x7x365 usage even running write-intensive levels for at least five years. Typical client usage is expected to be much lower, especially regarding the average percentage of writes, and thus drive lifespan can be much longer.
|Product feature||SAS SSD||PCIe SSD|
|Model supported||POWER6 and POWER7||POWER7|
|SSD units||177 or 387 GB/drive||177GB/module|
|Supported servers||POWER6 and POWER7||710, 720, 730, 740, 750, 755, 770, 780|
|AIX support||5.3 or later||5.3 or later|
|IBM i support||6.1 or later||6.1|
|Linux support||SUSE 10
RHEL 4.5 or later