Talked to Nimble Storage a few months ago. The 1st time they sounded cool and now I know why.
What they do
Nimble builds a converged storage appliance out of commodity hard drives and SSDs that offers high performance – is there any other kind? – and iSCSI, backup, a form of dedup and WAN replication. The pitch is EqualLogic & Data Domain merged into a single low-cost appliance. Only better.
- iSCSI + dedup
- Capacity-optimized snapshots
- SATA + flash instead of high-rpm drives
- Can run off a remote snapshot
EL & DD sell a lot of kit, so this could work.
Claim to fame
Cache Accelerated Sequential Layout is what Nimble calls their secret sauce.
CASL combines a variable block size, in-line compression, application-specific block sizes and checksum and compression data kept in the block header. They coalesce the blocks and only write in full stripes to disk.
The box has a large flash-based cache where the full stripe writes are also written, overcoming the small write performance hit that flash shares with parity raid. This also insures a high percentage of cache hits on the first read.
The system maintains an index of where all the blocks are written. Typically, this index is also held in flash for maximum lookup performance.
App-specific block sizes
Nimble uses of variable block sizes to improve performance. For example, the last three versions of exchange have all used different block sizes. CASL recognizes the different versions of Exchange and dynamically adjusts its block size to the best fit.
They claim a 2x performance advantage on Exchange databases.
They take the variable size blocks then coalesce those blocks into big chunks and write to flash. They write in large blocks – full block writes to flash and in full stripe writes to disk. Result: fast reads & writes across both media
Their page sizes are variable but small, ranging from 4KB to 64KB. The greater granularity means that frequent snapshots are much smaller than large page size systems like EqualLogic.
The StorageMojo take
There’s no reason that data protection should be separate from data storage. We’ve been moving towards integration since the CDP craze.
The average business wants to store and protect their data and they don’t want to spend much time or money on it. Nor should they.
With powerful commodity processors and nickel-per-GB storage there’s a huge market for a box that – or 2 or 3 boxes – that
- Stores terabytes of data
- Protects that data with local replication and frequent snapshots
- Auto-connects to cloud storage for DR and archiving
- Doesn’t confuse users with LUNs and stripes
- Offers Time Machine like data recovery to end users
It will look like magic – as any sophisticated technology should – and you’ll buy it at Office Max. As with any volume product the key will be architecting to maximize the user experience at an affordable price point.
Nimble certainly has the right idea.
Courteous comments welcome, of course. I don’t know which analyst the Nimble guys are blowing their money on, but it isn’t me.