Aurélien, I did not know which parallel issue you wanted to address. Based on previous comments in the thread I assumed it was not a simple edit situation.With FFT and other fractal analysis you are considering is very GPU/CPU intensive. Glad it is you and not me :) I have actually done parallel processing across servers using java. It definitely helped performance, but the software headaches were very extensive. We needed very specific use cases to justify the development costs and also the data transfer costs to move the processing. Let me know if you want the high level design on how it worked. We had two methods. One was ask based the other was offer based. Tim ------ Original message------From: Aurélien PIERREDate: Thu, Nov 2, 2017 8:23 PMTo: Cc: darktable;Subject:Re: [darktable-dev] Darktable + Cloud-computing
Tim, I think you miss the point. Doing parallel computing in your garage is possible, but it won't help if your I/O is slow, which is the case if you plug desktops PC in a farm. You just have to open darktable -d perf -d opencl to understand that most of the time spent during an image export is lost in GPU/CPU data transfers, when you copy the RAM in the CPU/GPU registers back and forth. What you need to do is parallelize on "close" cores to reduce the memory copies and work in registers as much as possible. The context of my question is I'm currently working to implement blind deconvolution for DT, and this process is not a filter but an equation solver that minimizes both the blur and the noise to find the minimal-energy image. This is something your CUDA GPU is not ready for, and needs several hours for large blurs on large images. Similarly, I'm investigating the possiblity to refocus images. We are talking about FFT, convolutions products, gradients computations, and so on with iterative processes, and I'm still not sure wether these functionnalities fit into a general-use software like DT. And if they do, you may not like the computing time. Aurélien PIERRE aurelienpierre.com Le 2017-11-02 à 20:05, steve a écrit : Worth a look at this first: https://www.youtube.com/watch?v=xuuiUhMr-lQ On 11/02/2017 08:01 PM, n61...@gmail.com wrote: Instead think of how many people have multiple computers at home. I have a desktop, a laptop, my wife has laptop, kids.... Most homes have more than one computer. For some of the more complex stuff it would be interesting to potentially off load to a local spare machine. I know audio systems do this for virtual instruments (brother is a hobby audiophiles) Tim ------ Original message------ From: Steven Adler Date: Thu, Nov 2, 2017 7:08 PM To: Aurélien PIERRE; Cc: darktable; Subject:Re: [darktable-dev] Darktable + Cloud-computing My PC is more than capable of processing photos and from what I've seen of v2.3, the new GPU support in Darktable makes processing much much faster. Cloud based GPU support would be great for advanced AI algorithms for things like auto background replacement. But still GPUs are advancing rapidly and I doubt we will need cloud GPU augmentation for some years. On Nov 2, 2017 6:17 PM, "Aurélien PIERRE" <rese...@aurelienpierre.com> wrote: Hi, as top-notch image processing algorithms become more and more demanding in computing power, but often highly parallelizable, and pictures resolutions double almost every 5 years (now 52 Mpx for the Canon 5DS R, 45 Mpx for the Nikon D850), most computers become hardly enough to just open the pictures. Let alone apply complex filters on them… Serious amateurs and pro may want to buy expensive workstations but… Cloud-computing solutions like Amazon EC3 gives you remote access to Linux instances with Nvidia GPUs for 0.76 US $/hour (g2.2 instances, 8 vCPU). The instances are scalable in size automatically and several Linux distros are provided (Ubuntu, Debian, Red Hat, CentOS). At this price, you get the price of your killer PC (5000 $) in more than 6500 hours of use. That's 5 years of working-time (assuming 48 weeks/year, 35 h/week, because I'm French). So… what do you think of having the heavy filters processed in Darktable through the servers of Amazon or anybody else instead of having to break the bank for a new (almost) disposable computer ? Possible or science-fiction ? How many of you don't have a 1MB/s or faster internet connection ? How difficult would it be to code ? Full disclaimer : I have no previous experience in cloud computing and no Amazon shares. -- Aurélien PIERRE aurelienpierre.com ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org