Teradata adds flash, denser packaging for BI appliances
More data chewing per square foot
In general, the 80-20 rule applies, says Gnau, with about 20 per cent of the data using up about 80 per cent of the aggregate I/O. "You are always looking at last week's data, which is hot, and then comparing it to the year-ago data, which was cold, then gets hot for a while, and then gets cold again."
Because moving this data manually from disk to SSD and back again would be a nightmare, Teradata has cooked up a little something it calls Virtual Storage, which tracks the hotness and coldness of the data at a block level and automatically moves it back and forth between the media based on the demand from the queries smacking against it. This software was first released in the Teradata clustered database two years ago, according to Gnau. "This is not some vaporware," Gnau says emphatically. "It is out there in the field and it works."
Rack for rack, the Active EDW 6680 flash-enhanced appliances have about four times the throughput of the new Active EDW 6650 appliances; the 6680s have less capacity and user space, of course, but significantly higher I/O for a portion of their data.
Gnau says that a few customers have already installed the Active EDW 6680 flashy appliances, and that is is aimed at the belly of the market where flash will help on some queries – not at the Extreme Performance Appliance 4600, where the "all the customer's data is hot, all the time". Teradata is also using the 6680 appliances on the systems that track its quality metrics and manage its supply chain for its manufacturing operations.
While you can mix the Active EDW 5650 and 6650 nodes in a single Teradata cluster, it is not advisable to mix the 6680 flash-enhanced nodes with node that don't have flash because, as Gnau put it, in a shared-nothing cluster, the cluster only performance as fast as its slowest node, so the 6680 nodes would be tapping their feet about three quarters of the time.
While Teradata did not release pricing information for the two new appliances, Gnau did give some guidance. The Active EDW 6650 costs less than the 5650 appliance announced last fall. The flash-enhanced Active EDW 6680 costs about the same as last year's 5650 appliance, but because it can do more work, it yields a much better cost per query than the 5650 did. The Active EDW 6680 has about a 75 per cent reduction in data center footprint and power consumption compared to a 5650 appliance yielding the same performance. ®