Nimble Storage Revisited: The CS700 and Adaptive Flash
Back in 2010 I noticed with this blog post the entry of Nimble Storage into the storage market. With their release of their new CS700 line and what they call Adaptive Flash, I figured it was a good time for a second look.
Before we look at the new offerings a quick refresh on Nimble Storage’s CASL architecture would be in order. CASL stands for Cache Accelerated Sequential Layout and Nimble describes the key functions here:
CASL collects or coalesces random writes, compresses them, and writes them sequentially to disks.
Nimble states that this this approach to writes can be “as much as 100x faster” than traditional disks. The image below is a bit fuzzy, but if you click to expand it should be readable.
It is important to note that both the compression and the automated storage tiering to flash is inline (no post-process or bolt-ons) which adds additional efficiencies. Also features such as snaps, data protection, replication and zero-copy clones are included.
For more details on CASL (including a 75 minute video deep dive) visit Nimble Storage’s CASL page here: http://www.nimblestorage.com/products/architecture.php
New Offering: CS-700
The CS700 is the new model which features Ivy Bridge processors, 12 HDDs and 4SSDs for a hybrid storage pool Nimble claims is up to 2.5x faster than previous models, with up to 125K IOPS from just one shelf.
Now you can buy expansion shelves for the CS700 including an All-Flash shelf and this is where something called “Adaptive Flash” kicks in. The All-Flash shelves host up to 12.8TB of flash each in a 3U shelf and are used exclusively for reads.The product materials on Adaptive Storage I found to be a bit light on technical details but from what I can discern some of the secret sauce is provided by a back-end cloud engine.
Nimble Storage has a robust “phone home” feature called InfoSight which sends health, configuration and utilization information to cloud services for analysis. Several vendors do this, but the twist here seems to be that they are using the resources of the cloud based engine to “crunch” your utilization data and send guidance back to your controllers on how they should be leveraging the flash tier. In summary the big idea here seems to be that leveraging greater computing resources “big data” style in the cloud can make better decisions on cache allocation and tuning that the controllers themselves.
The Big Picture
Nimble uses a scale-out architecture to scale out storage nodes into clusters. Nimble Storage claims that a four (4) node cluster with Adaptive Flash and support a half-million IOPS.
Below is a table (created by Nimble Storage) which position the CS700 in a 4-node cluster against EMC’s VNX7600 with ExtremeIO. I’d like to see an independent comparison but it appears Nimble Storage may be on to something with this architecture.
All-Flash arrays are nice but they aren’t the only game in town. Nimble Storage seems to have a compelling story around a hybrid solution which is driven by both controller software, as well as back-end software hosted on cloud services.