AnandTech: AMD's dual core Opteron & Athlon 64 X2 - Server/Desktop Performance Preview

Multitasking Scenario 1: DVD Shrink

If you've ever tried to backup a DVD, you know the process can take a long time. Just ripping the disc to your hard drive will eat up a good 20 minutes, and then there's the encoding. The encoding can easily take between 20 and 45 minutes depending on the speed of your CPU, and once you start doing other tasks in the background, you can expect those times to grow even longer.

For this test, we used DVD Shrink, one of the simplest applications available to compress and re-encode a DVD to fit on a single 4.5GB disc. We ran DVD Decrypt on the "Star Wars Episode VI" DVD so that we had a local copy of the DVD on our test bed hard drive (in a future version of the test, we may try to include DVD Decrypt performance in our benchmark as well). All of the DVD Shrink settings were left at default including telling the program to assume a low priority, a setting many users check in order to be able to do other things while DVD Shrink is working.

We did the following:

1) Open Firefox using the ScrapBook plugin loaded locally archived copies of 13 web pages; we kept the browser on the AT front page.
2) Open iTunes and start playing a playlist on repeat all.
3) Open Newsleecher.
4) Open DVD Shrink.
5) Login to our news server and start downloading headers for our subscribed news groups.
6) Start backup of "Star Wars Episode VI - Return of the Jedi". All default settings, including low priority.

This test is a bit different than the test we ran in the Intel dual core articles, mainly in that we used more web pages, but with more varied content. In the first review, our stored web pages were very heavy on Flash. This time around, we have a much wider variety of web content open in Firefox while we conducted our test. There is still quite a bit of Flash, but the load is much more realistic now.

DVD Shrink was the application in focus. This matters because by default, Windows gives special scheduling priority to the application currently in the foreground. We waited until the DVD Shrink operation was complete and recorded its completion time. Below are the results:

DVD Shrink + Multitasking Environment

As we showed in the first set of dual core articles, tests like these are perfect examples of why dual core matters. The performance of the single core Athlon 64 FX-55 is dismal compared to any of the dual core offerings. You'll also note that the Athlon 64 X2 4400+ completes the DVD Shrink task in less than half the time of the higher clocked single core FX-55. The reasoning behind this is more of an issue with the Windows' scheduler. The problem in situations like these is that the Windows scheduler won't always preempt one task in order to give another its portion of the CPU's time. For a single threaded CPU, that means that certain tasks will take much longer to complete simply because the OS' scheduler isn't giving them a chance to run on the CPU. With a dual core or otherwise multi-threaded CPU, the OS' scheduler can dispatch more threads to the CPU, and thus, is less likely to be in a situation where it has to preempt a CPU intensive task.

In this test, the Athlon 64 X2 4400+ does better than the Pentium D 840, but the Extreme Edition manages to offer slightly better performance. A faster X2 shouldn't have much of a problem remaining competitive, however.