Bottleneck problem

Beast of a machine, lower fps than normal.

I’ve been using VVVV for the last few months and it’s been brilliant. Insane resolution across multiple displays at a buttery smooth 60fps with most of the machines I’ve run it on. However, when I put it on the final hardware, I had huge slowdowns on some normally fine operations.

What I’m doing is using the Ex9 player patch with a sequence of 1600x2400 jpeg images. It can run mostly black images (100kB), but high-detail images (1.1MB) make it slow down and stutter hugely. At the start, on the first few seconds, I still get an easy 60fps, but as the sequence goes on, it drops to 7-8fps.

The machine I’m running it on has two of the Quadro k5000 graphics cards, 64GB of RAM, four 500GB SSDs in a RAID 5 configuration, and an Intel Xeon E5-2650. By all measures, a beast of a machine.

I’d thought it was a hard-drive read speed issue, but on testing, it can do 6GB/s. Anyone have any idea what might be going wrong? Any thoughts would be greatly appreciated :)

I’d start by monitoring your graphics card usage. Use GPU-Z . Keep eye on memory usage.

also the help patch of PerfMeter will tell you what all those coloured bars mean.

i’d recommend not to stream jpeg-sequences but to convert them to dds (uncompressed RGB or a dxt codec), ideally with image dimensions that are a power of 2.

while jpegs have to be decompressed on the cpu and can only then be transferred to the GPU-memory for display, the dds format was made for direct loading into GPU-memory (and if you are using DXT compression, it can be decoded directly on the GPU).

even though your machine is a beast, the jpeg decompression might be a bottleneck.

try these for converting your graphics:

Sounds similiar to the issue described here:
Have a look through the tips the community gave and see if it helps.

If not my question besides those I’ve posted in the above mentioned thread would also include:

  • Did you run the same setup on your development machines - in your first paragraph you say everything was running smoothly at 60 fps.
  • What image format are you using? Any difference if you try with an uncompressed stack (like bmp or tga)?