3PAR Systems Boost Low-End Storage

 
 
By Henry Baltazar  |  Posted 2004-03-15
 
 
 

The X-series InServ S400 and S800 storage servers from 3PARdata Inc. deliver impressive scalability and flexibility by harnessing the companys unique InSpire architecture and its InServ Storage Server software. The S800 is a bigger version of the S400; both products shipped this month. Both servers include X-Series controllers. The S800 has a larger backplane with room for eight storage controllers; the S400 holds a maximum of four.

Pricing for an entry-level X-Series InServ S400 with two controller nodes is $99,000 and includes all hardware and software and a three-year hardware warranty. This configuration includes 1.2 terabytes of raw capacity using 16 73GB drives and four host connections. The S800 backplane is similarly priced.

Upgrade pricing is $1,100 per additional host port and 1.25 cents per additional megabyte of storage.

Shops that expect to see significant storage growth should investigate the S800. IT managers who need a test system or storage for a workgroup will probably find the S400 a better fit.

By using a high-speed, full-mesh, passive-system backplane, which can carry data among controller nodes at an impressive 1GB-per-second performance rate, the InServ S800 can scale up to support 378.4 terabytes of raw capacity and eight controller nodes in a single system. By contrast, the smaller S400 chassis can have only two or four controller nodes and scales to 189.2 terabytes of raw capacity.

This is the first time weve seen a storage system with a backplane like this: The 3PAR InSpire architecture has more in common with ultra-high-end servers (supercomputers) than with other storage systems.

Compared with rival systems such as EMC Corp.s Clariion and Hitachi Data Systems Inc.s Thunder 9500 V Series, the scalability and overall functionality are impressive.

RAID-Ing Storage

3PARs inserv storage server storage virtualization software, which is included with these systems, is equally interesting.

The software, which also shipped earlier this month, divides physical disk drives into pools of 256MB parcels, which 3PARdata calls "chunklets." When a logical drive is created, the InServ Storage Server applies RAID functionality across dispersed groups of chunklets.

By default, the InServ Storage Server disperses the chunklets over several disks and controllers to take advantage of the architectures parallelism.

For example, instead of having a 500GB logical disk spread out over 10 disks, the InServ Storage Server will allocate logical disks over dozens of chunklets on different physical disks. As a result, each logical disk runs faster because there are several spindles (hard drives) available to process requests. Fibre Channel throughput is maximized because the data is running through multiple Fibre Channel loops and controllers.

For further customization, 3PAR InServ Storage Server can decide which portion of a disk to use when selecting chunklets. For example, if an application demands high throughput and primarily performs sequential reads and writes, 3PAR InServ Storage Server can be configured to use the outer ring of each drive for maximum performance.

3PAR InServ Storage Server includes optional, built-in thin-provisioning capabilities, which trick servers into thinking they have more storage than they really have.

Using thin provisioning, we could assign virtual volumes to test servers that were larger than the physical capacity of our system. As storage demand increases, the 3PAR InServ Storage Server takes storage space from a common buffer pool and automatically assigns it to the virtual volumes to meet users growing needs.

Thin provisioning enables IT managers to start with a modest storage system and gradually buy more storage as their organizations needs increase.

Disk Issues

The hard drives in the 3par InServ Storage Server are contained in magazines (each containing four drives). If a disk goes down, an IT manager has to remove the entire magazine and replace the bad drive. We were disappointed to encounter this process, because most comparable arrays have hot-swap drive enclosures that enable IT staff to replace one drive fairly easily.

The 3PAR InServ Storage Server has a logging mode that captures transactions when doing a drive replacement operation. Despite the arduous magazine-removal process, we found that replacing a bad drive and rebuilding an array was not terribly difficult in tests.

With 3PARs InServ Storage Server architecture, an IT manager can gradually scale up an enterprise storage system without ripping out and replacing legacy units—which is usually how IT managers upgrade their organizations from midrange to high-end storage.

The X-Series versions of the InServ S400 and S800 storage controllers include faster 2.4GHz Pentium 4 processors and more memory in the controller nodes than the non-X-Series versions.

The 3PAR InServ Storage System works with Solaris, Windows, HP-UX, Tru64 Unix, AIX, Linux and NetWare host systems.

The 3PAR InServ Storage Servers management interface was fairly easy to navigate. The GUI provides administrative granularity, which is useful for limiting the rights of users and low-level administrators. Using the interface, we could easily keep track of performance and capacity use. A command-line interface is also available.

Senior Analyst Henry Baltazar can be reached at henry_baltazar@ziffdavis.com.

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