EMC® recently released their XtremIO all-flash storage array for directed availability, introduced 4 new XtremSF PCIe flash cards with eMLC (enterprise multi-level cell) NAND storage to complement their current SLC (single-level cell) flash PCIe cards and discussed their XtremSW solution to support the cards.
New storage market view
EMC presented a chart that showed how they view the storage marketplace these days. The horizontal axis displayed a range of data services, the more complex services to the right and the vertical axis conveyed a range of system performance with highest performance on top.
From EMC’s perspective there is a huge chunk of the middle of the chart that is ideal for hybrid storage arrays. With a modest amount of flash, a large share of dense disk capacity and intelligent storage functionality, most customers will benefit from a hybrid approach. In the high performance, low data services section, XtremSF cards and software can meet these requirements. At the high performance, high data services segment of the chart, EMC’s new XtremIO all-flash storage array shines.
EMC’s perspective is that they can add value to PCIe cards with their XtremSW Cache software. In the future the XtremSW Suite will support active-active failover that is backed with EMC storage. Farther ahead, they see that multiple server PCIe cards can then be aggregated together to support a larger pool of server side flash. Ultimately, this all leads to a server-storage combination that controls all the flash in the data center, from server to storage, insuring that data is always at the best location to service application IO requests.
New XtremIO all-flash storage
Acquired last year and discussed at last year’s EMC World conference, XtremIO storage is reaching market availability. Previously, all-flash VMAX and VNX systems and hybrid disk and flash storage have been available but this is the first EMC storage specifically designed for all flash.
XtremIO contains no proprietary hardware, just advanced software functionality. XtremIO storage comes as a scale-out cluster of 5U controller nodes, called X-Bricks which consist of SSD storage, dual active/active controllers and host/cluster interfaces. Each X-Brick contains 7TB of useable flash storage, 4-8Gbps FC and 4-10GbE iSCSI ports. Infiniband is used as a cluster interconnect between controller nodes. An XtremIO cluster can contain one to four X-Bricks today, with plans to support eight and sometime later, sixteen and more X-Brick clusters. Performance scales up linearly with the number of X-Bricks.
XtremIO supports inline data reduction (deduplication and pattern elimination) sustaining high IOPS at sub-millisecond latency. With a single X-Brick array, performance for random 4KB block was 250K reads and 100K writes, with two X-Bricks double that and with a four X-Brick cluster 1M random 4KB reads and 400K random 4KB writes. These performance numbers were with pre-conditioned NAND storage and with all system functionality in operation, including thin provisioning, data reduction, and VAAI active.
Also, XtremIO global deduplication and thin provisioning are done on 4KB chunk basis. Device protection is not based on standard RAID levels, rather using a flash-specific algorithm developed internally by XtremIO. However, the system can tolerate multiple drive failures and still provide data availability. Currently, XtremIO data mirroring or replication is supported through VPLEX via RecoverPoint.
XtremIO storage systems will be limited to “directed availability” for the time being. This means that only qualified customers that plan to use the storage for approved use cases can purchase the system. These use cases include database OLTP, virtual server storage and VDI environments and over time more use cases will be added.
New XtremSF PCIe flash cards
EMC is introducing four new 25nm eMLC PCIe cards at 550GB, 700GB, 1.4TB and 2.2TB to complement their current SLC 350GB and 700GB cards. VFCache is being rebranded as XtremSW Cache. All these cards can be combined with XtremSW Cache software to provide a caching solution. Alternatively, the new PCIe cards can also be used as local storage within the server. The PCIe cards use 8X PCIe lanes to interface with the PCIe bus, has no IO impact during garbage collection, has an internal parallel design for multi-core workloads and as such, lowers CPU overhead versus competitive offerings.
Performance measurements against Brand F showed that both PCIe cards out-of-box performance fades over time but eventually XtremSF cards beats Brand F for sequential and random writes. For mixed IOPS (70:30 R:W) the new XtremSF 2200 (2.2TB) has double the IOPs for 4KB and 8KB blocks at a queue depth of 256 and has 2X the IOPs at the same latency as Brand F. The hero number for the new cards is 1.13M IOPS.
EMC’s flash juggernaut continues to roll on. The XtremIO solution looks intriguing and performance is enviable, especially with active inline deduplication. But we will need to see more how this holds to real workloads.
The new XtremSW Suite software road map looks interesting as well. Comparing performance of PCIe cards using “conditioned” NAND memory follows SNIA guidelines but is seldom used in practice, so kudos to EMC for doing so. Their software roadmap seems aggressive but it all depends on delivery now.
[This storage announcement dispatch was originally sent out to our newsletter subscribers in March of 2013. If you would like to receive this information via email please consider signing up for our free monthly newsletter (see subscription request, above right) and we will send our current issue along with download instructions for this and other reports.]
Silverton Consulting, Inc. is a Storage, Strategy & Systems consulting services company, based in the USA offering products and services to the data storage community.