Linux Can, Linux SAN

This decision to favor Intel/Linux enabled NuTec to create a lower cost structure with industry standard hardware, taking advantage of the improved FP (Floating Point) performance of Intel Pentium 4 processors, especially beneficial for their intensive graphical image processing requirements. The Linux route also eliminated the NFS bottleneck, and provided data sharing with SAN performance – with a CFS (cluster file system) on the SAN having the ability to scale to hundreds of nodes with minimal management.

NuTec adopted Minneapolis-based Sistina Software’s GFS (Global File System) Linux cluster file system. Its cluster nodes physically share storage over fiber channel or shared SCSI, and while each node thinks the file system is local, file access is synchronized across the whole cluster.

In effect, GFS can pool storage onto cheap, efficient machines. NuTec’s system resides on a Fibre Channel SAN infrastructure from LSI logic for high I/O performance. Processing consists of 350 dual processor P4 based nodes, providing 750 CPU’s running on Linux, each one four times faster per box than the previous AIX processors.

The following table, prepared by NuTec, compares the two systems:

Metric UNIX/IBM Linux/Intel
Performance
  • Bottlenecked by NFS
  • OK for single node
  • Performance cut by more than half at large scale
  • No bottlenecks
  • I/O at full SAN speeds
  • Performance scales linearly to hundreds of nodes
Cost
  • Costly proprietary hardware
  • Large footprint
  • Low cost industry standardservers
  • 1/10 the footprint
Management
  • Large administrative effort-many nodes to maintain
  • Fewer nodes to maintain
  • Administrators cut from four to two

One of the main challenges NuTec experienced in the changeover was porting imaging software from UNIX to Linux. Though there were risks involved, the company saw it as an opportunity to reduce costs and management, and they made the transition in just four weeks.

As a result, definite cost savings have been achieved. The headlines are 50 percent fewer administrators and a 90 percent reduction in data center space needed, down from 10,000 to just 1,000 sq ft. “The bottom line is overall cost savings of 84 percent, including hardware and software,” said Gajawada. “And, as a bonus, a higher adoption of Linux elsewhere in the company as a direct result of this implementation.”