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Wednesday December 14, 2005

I need to follow my own advice

Last week, when the Sun Fire T2000 system was officially launched in New York and London, we had our own mini-event in Austin, where there are a lot of chip designers working on Niagara technology. As part of that, we demonstrated the Sun Fire T2000 running side-by-side with a Dell PowerEdge 6850, which we believe to be about the best system that Dell has to offer. It was fully loaded with four 64-bit Xeon processors at 3.2GHz and 32GB of memory (not to mention a list price over $7000 higher than a fully-loaded 8-core T2000, also with 32GB of memory). Since I put the demo together, we were demonstrating our Directory Server using LDAP authentication performance as our metric. Although we do have a Shockwave Flash version of that demo, I haven't yet gotten permission to post it here, so I'll play it safe and avoid posting exact details from those tests. But I will say that the Directory Server on the T2000 was able to achieve quite more than two and a half times the performance of the server on the Dell system. And since we also had the systems running on power meters, we were also able to show that the Dell PowerEdge 6850 was drawing about two and a half times the power of the Sun Fire T2000. Plus, with a height of 2 rack units, the T2000 only uses half the space of the 4U 6850. If you put all those together, you've got a pretty wide SWaP (space, Watts, and performance) gap between them.

Earlier today, I was asked to update the test so that it would also include results from the Sun Fire V40z. The version we have in our lab was the top of the line at the time we got it with four Opteron 850 CPUs, but since then the dual-core versions have come out but we haven't gotten our hands on them yet, much less the new Galaxy systems. Nevertheless, they're still pretty impressive systems so we wanted to include them in the mix to see how they fared against the top-of-the-line system from that other company.

I installed the server, gave it our usual tuning, imported a test data set, and started it up. After priming the caches, I threw it into the mix but was disappointed to see it delivering quite a bit less than half the performance of the Dell system. Sure, on the surface it might seem reasonable given that the Dell system had eight cores rather than four, and its Xeon CPUs were running at 3.2 GHz rather than the 2.4 GHz Opterons, but it just didn't feel right.

And then it hit me. In my haste I forgot to update the start-slapd script so that the server would use the libumem memory manager and the fixed-priority scheduling class. It didn't take that long for me to realize it, but given that I wrote about it just last week it is a little embarrassing. Nevertheless, I quickly corrected the problem and was much happier with the results. It was now delivering more than double the performance of the Dell PowerEdge 6850, and it was actually a six-fold improvement over what it had been just moments before.

So now our demo shows two Sun systems that are faster, cheaper, use less power, and take up less space than the best that you can get from Dell. The T2000 does beat out the V40z in all of those categories, but we weren't testing the top-of-the-line V40z and perhaps the dual-core version could give the T2000 a run for its money. But come to think of it, our T2000 only had a 1GHz processor (whereas the version shipping to customers is running at 1.2GHz). At any rate, I guess that's a pretty good problem to have.

Posted by cn_equals_directory_manager ( Dec 14 2005, 01:21:35 AM CST ) Permalink Comments [1]