Exploring Hyper-threading Performance - Benchmarks Continued...

When I was sitting around deciding what Windows benchmarks I wanted to run for Part 1 of this article, I decided that I wanted another synthetic benchmark that simulated several different situations. There are several popular suites available, and I ended up going with PCMark 2004. Reason being it's relatively well-known and easy to acquire.

It incorporates things like file compression and encryption and even divx encoding performance. It will even take advantage of multiple processors.

Woah, big graph. Hyperthreading gives us an ~12.4% performance boost here. We'll take it.

We've always been rather enamored with Cinebench here at 2CPU.com, so its inclusion here is certainly not surprising. Obviously when hyper-threading was disabled on my P4 test system, I was unable to run the Multiple CPU portion of Cinebench's rendering benchmark.

Xeons have always ruled the roost in Cinebench and that doesn't look like it's going to change anytime soon. Look at how they scale here from 1-2 physical processors when hyperthreading is disabled. That appears to be a gain of 86%. Enabling HT on the Xeons gets us a whopping 110% improvement in performance as we scale from a single processor to multiple processors.

The uniprocessor P4 box doesn't see such a dramatic improvement, but it does pocket a 18% increase in performance.

Hooz always loves putting on his magical video encoding cap and crawling into his secret laboratory to brew up another benchmark for us. Since DivX encoding seems so last year, we've replaced it with a fancy DVD encode.

We'll be taking an episode of "Sex and the City" and using TMPGEnc to encode the interlaced MPEG2 video file to a DVD compliant video stream. (2-pass VBR with a minimum bitrate of 0, maximum of 8000 and average of 4000). We'll frameserve it from AVISynth with no filtering, cropping or resizing.

This really shows us what hyperthreading lets the P4C accomplish. Our Xeon test system certainly won the race but hyper-threading didn't have as much to do with it as we'd like. It accounted for a ~11% decrease in overall encode time. The P4C test system shows a remarkable 30% decrease in overall encode time. If HT will knock 17 minutes off a relatively short video encode, what is it going to give you if you're dealing with projects so big that they take days to encode? If you're looking to upgrade your renderfarm, maybe several P4Cs housed in Shuttle XPCs should be on your wishlist.

Let's move onto my conclusion. After spending so much time with these HT graphs, I feel relatively qualified to provide some analysis on our results and draw some conclusions.