In the tests, an i5 Model 595 with a quarter of its full complement of 64 1.65-GHz processors was able to sustain 175,000 Domino R6 Mail users, processing 258,403 NotesMark transactions. Why IBM did not test a full-blown 64-way is a bit of a mystery, but whenever vendors don’t put the pedal to the metal, it leads us to believe that they are trying to hide some scalability issues in their machines.
The i5 Model 570 tested in October was able to handle 165,000 R6 Mail users on its 16 Power5 processors, cranking through 242,835 NotesMarks. By the way, IBM has stopped giving prices for the iSeries and i5 configurations under test, thereby making price/performance comparisons with all other platforms not possible (unless you want to price a configuration yourself).
While we are convinced that the i5 Model 570 and Model 595 are great boxes on which to run Domino, IBM’s announcement of these i5 test results seem to be aimed more at showing the i5 dominating in a place where it does not intend to do a p5 benchmark and where no other vendor is testing similar big iron boxes. And not giving out prices is very suspicious. All of this makes it hard to say how well the i5 is doing compared with its rivals.
Incidentally, on the R6 iNotes benchmark, the i5 Model 570 supported only 28,500 users, the same number that the 32-way iSeries Model 890 did when it was tested in June 2003 on the R6 iNotes test. This is about what you would expect, given the relative power of the i5 Model 570 and the iSeries Model 890.
However, what you would not expect, unless you looked at the report, is that a Sun Microsystems Inc Sun Fire E2900 server with 24 UltraSparc-IV processor cores could handle about 20,000 R6 iNotes users, and that a Sun Fire V880 with 16 of the same cores could handle 14,000 users. In terms of per-processor performance, the Sun boxes are a lot closer at a two to one core count than on workloads like the TPC-C test, where it takes three to four Sun cores to match a Power5 core.
