We have been working on another mnesia backend plugin, based on leveled. This would use much less ram than the mnesia backend.
But beware: this is work in progress, at all levels (epoch, mnesia_leveled and leveled). We have been able to run the full test suite with it, though. A pull request exists (marked as WIP). Leveled is implemented entirely in Erlang, except for the (optional) lz4 compression. So if you have time and are willing to play with it, feedback would be much appreciated.
are you saying to basically check out “uw-leveled-backend” and recompile that ?
Basically, yes, but if you do it on the tinkerboard it would of course mess with your other tweaks. You might have better luck cherry-picking the changes (only 5 files affected).
But again, this is only if you want to be even more adventurous, but given that you’re trying to make it run on a tinkerboard in the first place, I thought it might be a fair assumption. 
Ok, but before trying that, I can’t get “bin/epoch” to start. Even thought “bin/epoch console” works perfectly.
Any suggestions on what to look at?
there is no erl_crash.dump nor any files in ./log/ so I am flying blind
Can you provide the printout of the following command?
bash -x ./bin/epoch start
Perhaps you could turn on some debugging by adding -vx to the #/bin/sh line in epoch?
Thanks for the suggestion, i just tried that but I don’t feel closer to understanding what is going on. O_O
That is why I asked for the printout. Could you also double-check the permissions of the folder and sub-folders of the release? Since no files are written it could be that the process simply can’t write to disk.
Sure. but if that were the case. wouldn’t it make “epoch console” fail and not just make 'epoch start" fail silently? oh. I can show you the output for sure. let me get to that machine
weird, this time it did create beam.smp on background and it works.