This is part I of my renderfarm experiment with Vue 5 Infinite build 278257. The chosen scene is the well-known Sponza. The goal of this experiment is to test V5I renderfarming abilities with stills (part I) and animations (part II). I hope it will be helpful for users who want to build a rendering farm, and also for e-on in order to improve this important feature. In this experiment, I used a 10 PCs renderfarm. I added each PC one after the other in order to record additional gains. Please be aware that V5i is relatively inefficient for still images parallel rendering when fast and slow PCs render at the same time. V5i does not determine at rendertime what are the "hardest" tiles to render, so if a very slow PC gets a very hard tile, it will continue to render long after all the others have finished. The renderfarm could actually render faster without the slowest PCs ! If all the PCs on the network have the same rendering power, of course the problem goes away. This problem could be dealt with simply by allowing manual allocation (by the user) of the number of tiles. With small tiles, even slow PCs would not get stuck too long, particularly in small renderfarms. I hope this option will be implemented in future versions of V5i. In each case the Manager was running on the fastest PC (Opteron). There was no noticeable delay to transfert the scene and the textures to the other machines on the network (a few seconds max). Sponza scene, ultra rendering mode, render to screen, 1024 x 768 pixels. PC 1 added (Dual Opteron 275 @ 2442 MHz) : 40 mn 24 s - 4 tiles PC 2 added (Dual Xeon @ 2800 MHz) : 33 mn 14 s - 9 tiles PC 3 added (Pentium 4C @ 3200 MHz) : 23 mn 08 s - 16 tiles PC 4 added (Pentium 4C @ 3400 Mhz) : 20 mn 14 s - 16 tiles PC 5 added (Pentium 4C @ 3300 Mhz) : 18 mn 34 s - 25 tiles PC 6 added (Pentium 4C @ 3300 MHz) : 16 mn 09 s - 25 tiles PC 7 added (Athlon 64 @ 2450 MHz) : 14 mn 58 s - 36 tiles PC 8 added (Athlon 64 @ 2400 MHz) : 14 mn 11 s - 36 tiles PC 9 added (Athlon 64 @ 2400 MHz) : 13 mn 33s - 36 tiles PC 10 added (Athlon XP @ 2250 MHz) : 12 mn 03 s - 49 tiles So the entire renderfarm completed the job 3.35 times faster than the fastest machine. It does not seem extremely impressive, but you will see that kind of result if one or two machines are clearly faster than the others. Note 1 : I had many crashes (V5I goes back to desktop) at the beginning of rendering. It seems to be a consequence of running repeated renderfarm runs without quitting and reloading the app first. The first time it occurred was after adding PC 5. I reloaded V5i and the Sponza scene and all went well. It seems that repeated renderfarm runs are difficult to handle by the program if you add new PCs one by one, and then render. If you add all the PCs you need in one run (this is generally the case) there is no problem. Note 2 : the display in the 'RenderCow Status' of the HyperVue network manager is rather strange. At the end of a render, you get the impression that many PCs are rendering the same tile, which is obviously not the case. I think it is a display bug. Has anyone noticed this ? (see screenshot) Part II of the experiment (in a few days if I find the time) will use the same protocol but with an animation. In that case images are not cut into tiles, but each frame of the animation is sent to a different PC. Efficiency should be better, as the complexity does not vary much between frames.

Ah, very interesting :) I'm especially interested in the animation test, as this is what I want to use V5I renderfarms for the most. I suspect you'll see a more impressive speed-up given that all machines will recieve the entire scene (not just part of the scene regardless of whether it's easy or hard to render), machines that render entire scenes faster will be free to rocket ahead while the slower machines will chug along.

Great information. Thank you.

I too get strange displays in the render cow status like yours. I also get the odd display when rendering stills where a tile like #4 which has been completed much earlier is re-rendered by all the machines at the end of the render cycle.

Constant rebooting is a must with these cows. I wonder how larger farms handle it. What makes you think that the display has a bug and that the cow isn't really rendering that frame?

Message edited on: 09/15/2005 13:49

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Maybe it's not a bug after all. When a hard tile is not finished by a slow machine it is probably given to every PC at the end. Maybe some tiles have problems and are re-rendered at the end also...