CPU Tests: Rendering

Rendering tests, compared to others, are often a little more simple to digest and automate. All the tests put out some sort of score or time, usually in an obtainable way that makes it fairly easy to extract. These tests are some of the most strenuous in our list, due to the highly threaded nature of rendering and ray-tracing, and can draw a lot of power. If a system is not properly configured to deal with the thermal requirements of the processor, the rendering benchmarks is where it would show most easily as the frequency drops over a sustained period of time. Most benchmarks in this case are re-run several times, and the key to this is having an appropriate idle/wait time between benchmarks to allow for temperatures to normalize from the last test.

Blender 2.83 LTS: Link

One of the popular tools for rendering is Blender, with it being a public open source project that anyone in the animation industry can get involved in. This extends to conferences, use in films and VR, with a dedicated Blender Institute, and everything you might expect from a professional software package (except perhaps a professional grade support package). With it being open-source, studios can customize it in as many ways as they need to get the results they require. It ends up being a big optimization target for both Intel and AMD in this regard.

For benchmarking purposes, we fell back to one rendering a frame from a detailed project. Most reviews, as we have done in the past, focus on one of the classic Blender renders, known as BMW_27. It can take anywhere from a few minutes to almost an hour on a regular system. However now that Blender has moved onto a Long Term Support model (LTS) with the latest 2.83 release, we decided to go for something different.

We use this scene, called PartyTug at 6AM by Ian Hubert, which is the official image of Blender 2.83. It is 44.3 MB in size, and uses some of the more modern compute properties of Blender. As it is more complex than the BMW scene, but uses different aspects of the compute model, time to process is roughly similar to before. We loop the scene for at least 10 minutes, taking the average time of the completions taken. Blender offers a command-line tool for batch commands, and we redirect the output into a text file.

(4-1) Blender 2.83 Custom Render Test

 

Corona 1.3: Link

Corona is billed as a popular high-performance photorealistic rendering engine for 3ds Max, with development for Cinema 4D support as well. In order to promote the software, the developers produced a downloadable benchmark on the 1.3 version of the software, with a ray-traced scene involving a military vehicle and a lot of foliage. The software does multiple passes, calculating the scene, geometry, preconditioning and rendering, with performance measured in the time to finish the benchmark (the official metric used on their website) or in rays per second (the metric we use to offer a more linear scale).

The standard benchmark provided by Corona is interface driven: the scene is calculated and displayed in front of the user, with the ability to upload the result to their online database. We got in contact with the developers, who provided us with a non-interface version that allowed for command-line entry and retrieval of the results very easily.  We loop around the benchmark five times, waiting 60 seconds between each, and taking an overall average. The time to run this benchmark can be around 10 minutes on a Core i9, up to over an hour on a quad-core 2014 AMD processor or dual-core Pentium.

(4-2) Corona 1.3 Benchmark

 

POV-Ray 3.7.1: Link

A long time benchmark staple, POV-Ray is another rendering program that is well known to load up every single thread in a system, regardless of cache and memory levels. After a long period of POV-Ray 3.7 being the latest official release, when AMD launched Ryzen the POV-Ray codebase suddenly saw a range of activity from both AMD and Intel, knowing that the software (with the built-in benchmark) would be an optimization tool for the hardware.

We had to stick a flag in the sand when it came to selecting the version that was fair to both AMD and Intel, and still relevant to end-users. Version 3.7.1 fixes a significant bug in the early 2017 code that was advised against in both Intel and AMD manuals regarding to write-after-read, leading to a nice performance boost.

The benchmark can take over 20 minutes on a slow system with few cores, or around a minute or two on a fast system, or seconds with a dual high-core count EPYC. Because POV-Ray draws a large amount of power and current, it is important to make sure the cooling is sufficient here and the system stays in its high-power state. Using a motherboard with a poor power-delivery and low airflow could create an issue that won’t be obvious in some CPU positioning if the power limit only causes a 100 MHz drop as it changes P-states.

(4-4) POV-Ray 3.7.1

V-Ray: Link

We have a couple of renderers and ray tracers in our suite already, however V-Ray’s benchmark came through for a requested benchmark enough for us to roll it into our suite. Built by ChaosGroup, V-Ray is a 3D rendering package compatible with a number of popular commercial imaging applications, such as 3ds Max, Maya, Undreal, Cinema 4D, and Blender.

We run the standard standalone benchmark application, but in an automated fashion to pull out the result in the form of kilosamples/second. We run the test six times and take an average of the valid results.

(4-5) V-Ray Renderer

 

Cinebench R20: Link

Another common stable of a benchmark suite is Cinebench. Based on Cinema4D, Cinebench is a purpose built benchmark machine that renders a scene with both single and multi-threaded options. The scene is identical in both cases. The R20 version means that it targets Cinema 4D R20, a slightly older version of the software which is currently on version R21. Cinebench R20 was launched given that the R15 version had been out a long time, and despite the difference between the benchmark and the latest version of the software on which it is based, Cinebench results are often quoted a lot in marketing materials.

Results for Cinebench R20 are not comparable to R15 or older, because both the scene being used is different, but also the updates in the code bath. The results are output as a score from the software, which is directly proportional to the time taken. Using the benchmark flags for single CPU and multi-CPU workloads, we run the software from the command line which opens the test, runs it, and dumps the result into the console which is redirected to a text file. The test is repeated for a minimum of 10 minutes for both ST and MT, and then the runs averaged.

(4-6a) CineBench R20 Single Thread(4-6b) CineBench R20 Multi-Thread

 

CPU Tests: Simulation CPU Tests: Encoding
Comments Locked

229 Comments

View All Comments

  • vyor - Monday, May 17, 2021 - link

    Worst case for Zen3 is matching Zen2. That's the *worst* case. Name a single actual workload it's slower in.
  • Otritus - Monday, May 17, 2021 - link

    Vermeer was consistently faster than Matisse, but Milan was not consistently faster than Rome. Cezanne is faster than Renoir in all but 1 subtest. All 3 comparisons are Zen 3 vs Zen 2. Also SPEC isn't an actual workload by the standards of it's something people run for work or entertainment. It's just a series of industry-standard benchmarks to evaluate the performance of processors. In all of the real workloads Cezanne wins.
  • mode_13h - Monday, May 17, 2021 - link

    > Milan was not consistently faster than Rome.

    Because the IO die is consuming too much power @ the higher frequency it uses in Milan. Not due to the cores, themselves.
  • Bagheera - Tuesday, May 18, 2021 - link

    Rocket Lake was well loved.... by who? it was universally panned by reviewers. the lower end sub-$300 i5 may be good value, but that's about it. the high end parts not only lose to Zen 3 but loses even to CML in some cases.
  • Makste - Monday, May 31, 2021 - link

    Take a sarcasm 😉
  • Hifihedgehog - Monday, May 17, 2021 - link

    Exactly. Generally, I find the results here very accurate here, but that needs serious attention.
  • vyor - Monday, May 17, 2021 - link

    I find that his Spec testing has gotten worse and worse over the years. Andrei honestly just don't know how to use the suite and it almost always makes some parts look better than others when they really shouldn't be. Just look at the M1 tests for that, where the single thread perf in SPEC vastly exceeds that scene in any other test.
  • Andrei Frumusanu - Monday, May 17, 2021 - link

    You're welcome to demonstrate what is flawed with actual technical arguments.

    The M1 exceeds because it's that good, we're missing it in many other benchmarks simply because they aren't ported to macOS or currently don't have data on them.
  • vyor - Monday, May 17, 2021 - link

    "it's just that good" except in every single case it isn't.

    Name a single workload where the spec results line up with application performance.
  • Ppietra - Monday, May 17, 2021 - link

    Single thread performance seems to align quite well with other tasks!
    Look at Cinebench single thread performance. Look at compiling performance. Look at javascript performance, etc, etc!

Log in

Don't have an account? Sign up now