A quick guide: How to install OpenCL for AMD GPUs on Linux Kubuntu 18.04 (and similar distro)

I did try ROCm, it was almost double the speed of Mesa/Clover OpenCL here at Einstein. However, OpenCL from 18.50 still outperformed ROCm by a few percent. Collatz was ok. Both had problems though on other projects, eg. Milkyway doesn't work at all. Both free implementations were ~30% slower than 18.50 legacy OpenCL at Primegrid.

I focused back in the AMDGPU-PRO driver and looked for the libraries that it needs to get OpenCL running on unsupported distributions and kernels. Arch Linux had a build script to extract the libraries from the official driver, I based my version for DEB based distributions around that:

http://kerbodyne.com/boinc/create_amdgpu-ocl-pkg.sh

Place the script with the driver archive of 18.50 in the same directory (I'm still working on automatic downloading from the official website), then execute the script. It unpacks the driver and extracts libraries from 3 different packages, then creates an installable package from these. So they can be installed/removed quickly, copied to other systems etc. I choose to provide a script here, so I don't (potentially) violate the license agreement by redistributing AMDs software on my server. The script will ask for sudo permissions in order to change the ownership of the files contained in the archive to root:root. Have a look at the code to confirm that it doesn't do any harm. I created it in an isolated environment, also tried it on my primary workstation, no harm was done running the script ;-)

I could get a Polaris and a VEGA card crunching on Ubuntu 19.04 with kernel 5.0.0 via this procedure. No success yet on pre-Polaris cards yet, I plan trying with an HD7950 tonight though, lets see.

Any feedback is welcome, I'd appreciate you reporting back in case it works or fails for you.

Thanks!

Darn it and here I installed 18.10.2 hoping it would work!! Oh well I will have to look thru my cd's and see if I have that older version or it's back to the download page.

I too had no joy loading amdgpu after a clean install of 18.04.2, but discovered (from a tip from Rick'sLab on GitHub), that if you first clean install Ubuntu 18.04.1, then update, there is no problem installing amdgpu 18.5 or OpenCL. The reason, I believe, is that 18.04.1 loads the Linux 4.15.0-47-generic kernel, which is retained after the update to 18.04.2, while a 18.04.2 clean install loads the Linux 4.18.xxxx kernel, which so far doesn't work with amdgpu.

With the current amdgpu 18.5-756341 driver package for Ubuntu 18.04, the on-line AMD documentation is not up to date. After ./amdgpu-install -y  and a reboot, I could only get OpenCL to install with ./amdgpu-install -y --opencl=legacy. (I didn't need the Vega drivers so didn't include =pal in my above example, and didn't need the --headless option.) In other words, ./amdgpu-pro-install -y --opencl=legacy didn't work.  There is no longer a separate amdgpu-pro-install script, so -pro is now an option within the new amdgpu-intstall script.

Also, amdgpu-uninstall won't work as documented because that script is now in usr/bin; run from there and it works fine (as I learned from many failed early installation attempts).

Ah, no, I didn't think of that. Tasks are crunching nicely at the moment, so I'm hesitant to fix something that ain't broke.  Same reason I haven't tried the new AMD amdgpu 19.1 drivers optimized for Ubuntu 18.04.2. I'll take the ignoble route and wait to hear from someone else those magic words, "yes, it works".  In case I get a fit of courage, though, is it necessary to uninstall amdgpu before updating to newer drivers?  What about OpenCL? - would that also need to be uninstalled before updating?