Kaminario has introduced the world’s fastest SAN storage, the K2. If time is money, this is for you.
Kaminario’s K2 is fast because DRAM, not disk, is the primary storage. DRAM’s low latency, high bandwidth and durability breaks the tight link between capacity and performance that disks and flash impose. No need for excess capacity to ensure enough IOPS, bandwidth or service life.
Kaminario is a software company. However, they configure customer systems and install the software to order. No home-baked integration here.
The basic hardware unit is a Dell blade server. The blade servers are either I/O directors or data nodes. The Dell server chassis is a passive box – no active components on the backplane – but some customers opt for dual chassis for redundancy out of caution.
The I/O directors use 8 gig Fibre Channel to servers and 10Gig/Ethernet to data nodes. The company says they can saturate both due to proprietary software optimizations.
Using FC switches, each I/O director can talk to multiple servers. Each I/O director can handle 150,000 random IOPS.
Each data node supports up to 288 GB of ECC DRAM. All the data nodes have battery backup and 2 disks for de-staging data to persistent storage. Background de-staging during idle time reduces backup times during power failures.
The minimum config is 2 I/O directors and 4 data nodes with 500 GB of capacity. That’s 300,000 IOPS. They’ve been tested to 10 nodes and 1.5 million random read/write IOPS with support for 16 nodes – and double the IOPS – reportedly coming soon.
Under the covers
The I/O directors are clustered so when 1 fails the others pick up the load. The switched back end 10Gig Ethernet enables all I/O directors to access all data nodes.
The replication default is 2 copies of all data on different blades. Plus copies on disk.
All this runs on standard Dell blade servers. No specialized, low-volume RAID controllers or power-hungry disk shelves.
The secret sauce is the software. Kaminario doesn’t say much about how they do what they do. In any high-performance cluster maintaining metadata coherence across nodes is one of the tough problems.
They did say they maintain hash tables that enable very short updates to all I/O directors after writes. I also suspect they also have implemented a low latency backend update protocol. Metadata serving is distributed across the cluster.
They must also have some creative ways to max out FC links. I’d like to know more.
With storage this fast they say you need little tuning. Lay LUNs across the data nodes and fasten your seatbelt. The software includes optimizations, like pseudo-random block layout to minimize contention, automatic load balancing and demand-based block replication.
If your app calls for it you can tune chunk sizes and set replication policies. Kaminario says K2 is much easier to manage than typical high-performance storage – you don’t have to worry about disk-induced issues like stride.
Management is kept out of the data path on a dedicated GigE network.
Kaminario says they have designed the product and their organization to provide mission-critical Enterprise support. The visible elements from configuration control and software installation to phone home and remote diagnostics back that up.
Who needs this?
If you are hammering a few TB of data for stock trading, real-time business intelligence or TLA government work, this could be the ticket.
If you have to ask. . . .
Kaminario has a unique approach: pay for performance:
. . . we price the solution based on the customer IOPS and capacity needs, so basically the way we present such a platform price is by $/GB/IOPS.
I *think* small configs start around $200k. For the performance market price is something like #7 on the list. The first 3 are performance/availability – 2 sides of the same coin, really.
This removes SPEC shadow puppetry between application requirements and storage performance. Of course, you have to know what performance you want. But anyone who’s performance tuning high-end arrays will know that.
The StorageMojo take
Kaminario is opening a new niche at the performance end of the market.
The current Big Storage vendors claim that they too can do a million IOPS. And they can, for millions. A price that makes a few TB of DRAM look cheap.
Since high-end disk – ≈$1/GB retail – makes up 5-10% of the cost of a high-end array, replacing disk with DRAM might be expected to double the cost of an array. But K2 does away with all the low-volume kit – controllers, shared cache, disk packaging and more – and replaces it with high-volume blade hardware. That lowers costs a lot.
Kaminario has opened a new niche: hyper-performance data storage. While a few TB doesn’t sound like much, it is more text than all but the world’s largest libraries place on miles of shelves.
The data arms race has kicked up another few notches. It is more competition for the big iron arrays where they least expected it: at the high-end of the market.
Courteous comments welcome, of course.