IBM Corp this week launched the expected enhancements to the 3990 Model 6 disk controller, which are thought to be the prelude to the company’s first foray into disk arrays. The company is making available enormous cache capacity of 1Gb, effectivly making the controller a sold-state store in its own right. New record cacheing techniques are offered, which complement and co-exist with the existing track cacheing, and, IBM reckons, means that the controller provides benefits even on applications not usually identified as having good cacheing characteristics. At the end of the year, even bigger cache of up to 2Gb, plus 64Mb of non-volatile store, will be offered. A new remote copy extended function is offered to improve disaster recovery. Two implementations, extended remote copy for asynchronous volume shadowing over Escon, and peer-to-peer remote copy for synchronous volume copying over Escon. The copy creation function of Dual Copy has been improved with the addition of multi-track staging and destaging algorithms to reduce the time it takes to establish a duplex pair. The 1Gb cache is available from the end of the month and was previously announced; the 2Gb cache, and a 1.5Gb option, are available at the end of the year at $816,000 for 2Gb, plus $3,840 monthly maintenance; it rents for $51,000 a month. The 64Mb non-volatile store sells for $80,000, also at year-end.
