I have got a high speed multi-channel data acquisition PCIE device that would benefit from allocating huge buffers for the dma controller. I have got a system with 48Gb of ram and I would like to lock down something like 20Gb dedicated to the dma controllers on this high-speed adc device.
running 64 bit kernel 3.8.0 kmalloc is limited to 4Mb bigphysarea patch hangs my system if I allocate anything above 1Gb could use mem=28G to lop off upper memory but it could get messy accessing that memory in user space as well as kernel
What would you suggest?