By Dave Simpson
This summer saw a spate of announcements in the high-end disk array arena. Following announcements by Compaq (which will resell IBM's "Shark" arrays), EMC, Hewlett-Packard, IBM, and Sun, Hitachi Data Systems (HDS) last month began initial shipments of its Freedom Storage 9900 array ("Lightning"), which succeeds the company's Freedom 7700E. (A version of the 9900 is resold by HP as the XP512.)
According to analysts, a key architectural differentiator is the 9900's 6.4GBps switching architecture (which compares to a shared-bus internal bandwidth of 700MBps on HDS' 7700E). The switched fabric architecture provides point-to-point connectivity between disk drives, cache and host interfaces. Separate connections are used for data and control paths. HDS claims a 4X to 6X performance improvement over the 7700E in small block transactions.
The 9900 can scale to 37TB using Hitachi's 73GB Fibre Channel disk drives, which will be in production in the fourth quarter. (The array is also available with 18GB and 47GB drives.) The dual-ported, 10,000rpm Fibre Channel drives can be configured in dual-active mode (e.g., both ports are active at the same time). Up to 32 Fibre Channel loops are supported, in addition to 2GB to 32GB of cache memory (vs. 16GB for the 7700E).
Pricing ranges from about $600,000 for a 1TB configuration to more than $12 million for a 37TB system. The arrays support OS/390, Unix (including Linux), and Windows NT. Volume shipments are expected next month.
All software that runs on the 7700E runs on the 9900, including ShadowImage, Asynchronous Remote Copy and NanoCopy. In addition, HDS has added a Dynamic Optimizer tool for automated tuning. For example, it allows administrators to adjust RAID levels and move logical volumes in the subsystem and cache. HDS also added NanoCopy support for Windows NT, Solaris, AIX, and HP-UX. (NanoCopy previously supported only OS/390 mainframes.)