Lotus Domino for i5/OS

IBM eServer i5 is the newest member of the iSeries and AS/400 family. It's built on the latest POWER5 and advanced Virtualization technologies from IBM. Like its older siblings, IBM eServer i5 delivers outstanding scalability as a Domino server. Certainly, this scalability comes from advanced technology and powerful processors. But it also comes from the unique architectural match between Domino and i5/OS.

By implementing Domino instances in i5/OS (OS/400) subsystems, the eServer i5 is able to fully leverage Domino partitioning without requiring multiple copies of the operating system or multiple copies of the Domino code. For example, for this benchmark result of 175,000 Notesâ users, we ran 27 Domino partitions in a single copy of i5/OS utilizing 16 POWER5 processors in a single server footprint. And we delivered average response time for those 175,000 concurrent users of 33 milliseconds (0.033 seconds) for the required 6-hour duration of the test. With these results, the eServer i5 beats its own previous records of 165,000 R6Mail users with 3 9ms response time on a 16-way model 570 server. Due to differences in the processor architecture of the 595 and 570 models, the 16-way 595 provides slightly more capacity than the 16-way model 570 even though the processor speed for both models is the same 1.65GHz.

175,000 users! That's almost unimaginable. But let's imagine it for a minute. Picture the IBM eServer i5 server sitting in the center of a room. It's flanked by 6 double-high racks to hold the 540 disk drives required to support the mail files for the 351,000 users in the Domino Directory (name and address book). This sleek powerful server is surrounded by 117 PC's, 116 simulating 1,500 users and one simulating 1,000 users to achieve an even 175,000 total users. For over 13 hours including ramp-up and steady state, these PC's bombard the eServer i5 server with e-mail requests, which it handles flawlessly:

Let's look at this amazing result from another perspective. Is it just a big gorilla that achieves big numbers because of sheer size? Actually, eServer i5 achieves excellent efficiency of resource utilization for configurations of different shapes and sizes.

The 16-way POWER5 configuration for this audit supported 10,937 users per processor. Earlier this year, we published a 24,000 R6Notes report on a 2-way IBM eServer i5, supporting 12,000 users per processor. These two results demonstrate near-linear scalability on POWER5 and i5/OS as we add processors to the same operating system and the same Domino instance. And both of them show a much better users-per-processor ratio compared to our own previous results with POWER4 technology and compared to any other currently published scalability results on other platforms. We see similar efficiency in the user-per-MHz ratio compared to other processors architectures.

These technology achievements are interesting -- even exciting. But what does it mean to real organizations who don't have 175,000 employees and don't try to eke out every last ounce of performance from their systems? The answer comes back to the match between eServer i5 architecture and Domino architecture. Organizations of all shapes and sizes can benefit from the ability to fully leverage Domino partitioning. It translates to fewer moving parts to pay for and to manage: physical servers, operating systems, Domino code. It means you can often add a new group of users or a new Domino application simply by creating another instance of Domino in a few minutes, instead of deploying another physical server with everything that implies. It means your administrators can spend their time delivering end user support and business value instead of managing a server farm.

This benchmark result is the latest example of IBM's commitment to the continued excellence of the iSeries family as a Domino server platform. Thanks for taking the time to read about it. If you'd like to learn more, please browse the other links on this Web site.