Later today, IBM will formally announce its upgraded AS/400e systems and servers, which use the new 64-bit Northstar PowerPC processor. The thirteen new AS/400s do not replace the existing line of Apache PowerPC AS/400e machines, which IBM announced last August, but rather extend that line. They also demonstrate IBM’s almost total commitment to marketing its AS/400e servers, which are optimized for client/server workloads, rather than its plain vanilla systems, which are used to run old-style green screen applications. Eight of the thirteen new models are high-end servers that are virtually indistinguishable from the RS/6000 S70 Blackbird servers that were announced by IBM in late July. These AS/400e models use the Northstar chip running at 262 megahertz, the fastest speed at which it is available and the same speed that is used in the RS/6000. In the AS/400 the Northstar chip is called the A50, in the RS/6000, the RS64-II, but don’t be confused, they are the same exact chip. Each Northstar processor is equipped with a relatively fast floating point unit capable of doing one operation per clock cycle, two integer units (rather than the one used in the Apache chips), 128 kilobytes of Level 1 cache (split evenly between data and instructions) and 8 megabytes of Level 2 cache (double that of the Apache models). The AS/400es using the fastest Northstar come in two hardware configurations, either an eight-way or a twelve-way model; the RS/6000s came in four-way, eight-way and twelve-way configurations. The high-end AS/400e models also use slightly different memory and I/O subsystems; the AS/400 has three high speed memory ports rather than the two in the RS/6000 and uses IBM’s proprietary SPD I/O connectivity rather than the slower industry-standard PCI interconnect common in Unix and PC servers. The upshot is that an AS/400 with the same number of Northstar processors does about 40 percent more work than the equivalent RS/6000. IBM hasn’t released TPC-C or SAP SD benchmark results for the AS/400 yet (they are in audit), but the twelve-way AS/400 should be able to crank through between 45,000 and 50,000 TPC-C transaction per minute and should be able to support about 4,600 SAP SD users. That’s a little less than twice the performance of last year’s Apache-based twelve-way. For more details, see Barbed Wire.
