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All-flash storage is the mainstream now when it comes to enterprise and midrange storage arrays.
All the big five storage array makers – Dell EMC, HPE, Hitachi, IBM and NetApp – key array products are primarily offered as all-flash, although hybrid flash with spinning disk and even all-HDD are options too.
Having said that, flash is where the key boundaries of innovation are being pushed.
NVMe flash drives are available as options in high-end enterprise arrays from Dell EMC, IBM and NetApp, with the latter claiming end-to-end NVMe out to hosts too. HPE bucks the trend by only using NVMe as connectivity for storage-class memory with Intel Optane as a cache layer.
Storage-class memory is planned elsewhere for inclusion in Dell EMC’s Powermax high-end arrays.
Standard across enterprise storage is IOPS that run into the millions and capacities that go to several tens or beyond of Petabytes (PB). So too are Fibre Channel and iSCSI connectivity to hosts, plus mainframe too in a small number of products, most notably from Dell EMC, IBM and Hitachi.
Also standard are dual controllers, replication, snapshots, encryption, thin provisioning and data reduction. When it comes to the cloud, all the array makers have some method of using the cloud as a tier, which we have gone into more detail about here.
In this article we’ll look at Dell EMC’s VMAX/PowerMax, Xtremio, Unity, SC, and PowerVault ME4 products, plus HPE’s 3PAR and Nimble arrays. In an accompanying piece, we look at Hitachi’s VSP F- and G-series, IBM’s FlashSystem, StorWize and DS arrays, plus finally NetApp’s AFF/FAS, Solidfire and E/EF-series.
VMAX and PowerMax: Dell EMC’s flagship enterprise storage arrays are aimed at high end SAN storage for block and file in open and mainframe environments, with the full range of advanced storage functionality.
Dell EMC part re-branded VMAX as PowerMax last May and with the new name came end-to-end NVMe flash storage in “flash bricks”.
PowerMax is aimed at large-scale, performance-hungry enterprise databases and analytics and AI/ML applications. Storage class memory – which adds a tier of fast storage between backend storage and memory is planned for PowerMax.
There are two PowerMax array products, the 2000 that offers up to 1.7 million IOPS and scaling out via 13TB bricks to a capacity of 1PB effective, while the 8000 offers 10 million IOPS and up to 4PB via scale-up/scale-out growth in 54TB or 13TB (for mainframe) bricks. Both claim under 300µs latency.
Meanwhile, VMAX continues to be sold, with F-suffixed models using drives that are SCSI-connected flash, the 250F and 950F.
Like their PowerMax offspring they are distinguished by performance and capacity, with the 250F offering up to 1PB with up to 1 million IOPS and the 950F up to 6.7 million IOPS and 4PB. Latency comes out higher than the NVMe-equipped PowerMax boxes at 500µs and 350µs respectively.
VMAX arrays are also available as hybrid flash and disk-equipped storage, in the 100K, 200K and 400K products. These range from around 500TB to 4.35PB useable capacity. All Powermax and VMAX arrays are 8Gbps and 16Gbps Fibre Channel-connected, plus Fibre Channel-over-Ethernet, iSCSI and FICON (mainframe).
Read more about the big five storage array makers
- NVMe flash offers blistering performance gains but so far the big five storage array makers have tended to opt for gradual implementations rather than radical new architectures.
- We look at the big five storage array makers' efforts to connect on-premise hardware with cloud storage and find automated tiering, on-ramps, and backup and archive capability.
Xtremio: Dell EMC’s all-flash block access SAN array product line is Fibre Channel, iSCSI and Ethernet connected.
The product line got a big boost in 2017 and was rebranded Xtremio X2. This saw a bunch of hardware and software upgrades that saw capacity scale to 1.1PB, or a claimed 5.5PB effective.
Xtremio X2 is based on X-Brick drive bays that can hold up to 72 drives and can be built into clusters of up to four nodes. The product line has a full range of enterprise storage features that includes data protection, thin provisioning and data reduction, with synchronous replication added in 2018.
Average latency is half a millisecond across the range, with IOPS figures that go from 430,000 for a single X-Brick up to about 1.7 million for a four-brick cluster. That’s for read-only. You can half that for 70/30 read/write workloads.
Unity: Dell EMC’s 2U format midrange Unity family launched in 2016 as a merger of the VNX and VNXe ranges. They come in hybrid and all-flash array formats (as well as a virtual appliance) and provide block, file and VMware VVols access via up to 16Gbps Fibre Channel and iSCSI. The all-flash F-suffixed products are the 300/350F, 400/450F, 500/550F and 600/650F.
Entry-level capacity on the 300/350F starts at 4TB and scales to 2.4PB, while the 600/650F can go up to 10PB. I/O performance ranges from around 100,000 IOPS in the 3-series arrays up to nearly 400,000, although that’s for read-only.
The Unity hybrid models leave off the F suffix, but scale to similar capacities. Unity got a software upgrade in 2018, and there is talk that it will be merged with Dell EMC’s SC family in 2019.
SC: Dell EMC’s SC family of midrange 3U SAN (iSCSI and Fibre Channel) storage arrays are firmly aimed at midrange customers and are an inheritance of Dell’s acquisition of Compellent in 2010.
SC arrays come as the all-flash SC7020F and SC5020F, which scale up to 4PB and 2PB respectively and I/O performance of around 1 million IOPS. There are also four hybrid flash arrays – the SCv3000, SC5020, SC7020 and SC9000 – which scale up to between 1PB and 6PB before data reduction and offer I/O of between 230,000 IOPS and 502,000 IOPS for 80/20 read/write workloads.
SC also got a software refresh in 2018, which Dell EMC claimed doubled IOPS for each array.
Powervault ME4: Dell EMC’s entry-level storage array comes as all-flash or hybrid flash in the 2U ME4012 and ME4024 (with 12 and 24 drive slots) systems plus the 5U ME4084 expansion enclosure.
It can be configured as direct-attached storage for PowerEdge servers or as SAN storage with 10Gbps iSCSI or 16Gbps Fibre Channel connectivity.
The arrays take SAS flash drives and nearline-SAS spinning disk and can scale up to 4 PB of raw storage with expansion shelves. Auto-tiering, disaster recovery, RAID support, replication, snapshots, thin provisioning and volume copy software are standard features.
Dell EMC publicity cites 332,000 IOPS, but that’s probably read-only.
3PAR: These enterprise storage arrays come in three models, with SAS drive connectivity for flash and spinning disk.
They comprise the StorServ 8000, 9000 and 20000 series SAN arrays. These are chiefly distinguished by capacity, and range from about 3PB to 6PB (15PB useable in the latter case), with claimed IOPS between 1 million and 3.4 million.
The 8000 provides capacity of up to 3PB, while the 9000 and 20000 series offer NVMe-accessed Intel Optane as a storage-class memory tier. Connectivity is 16Gbps and 32Gbps Fibre Channel and 10Gbps Ethernet for iSCSI across the board. HPE has said it will be holding fire on adoption of NVMe as backend storage until greater benefits can be realised.
Nimble: HPE acquired Nimble Storage in 2017. Arrays are all-flash and hybrid (Adaptive in the HPE branding) and are noted for their inclusion of InfoSight analytics.
Support for NVMe-connected storage-class memory was added in 2018, as with HPE’s 3PAR arrays. All-flash arrays use SATA SSDs and come in several models that range in capacity from a few tens of TB to around 1PB raw.
Adaptive flash arrays start at just over 200TB capacity and scale to 1.26PB raw.
All have Fibre Channel and iSCSI connectivity.