I'm NOT running Geth or any other wallet on the miners. I have dedicated systems for mining running Ubuntu 15.04, 64 bit desktop with ethminer compiled from cpp-ethereum. Motherboards/Processors range from Dual-core 2.5 to 3.4Ghz, to 3.6Ghz dual Xeon's, each has 8GB ram although a couple have 4GB ram. Each motherboard is running 2 GPUs. The GPUs include various quantities of R9 270X, R9 290, R9 290x, R9 295x2, R9 390, R9 390X and RX 480 gpus
The hard drives are small. I'm using 40GB and 80GB SATA hard drives on each system just because I have a ton of them and it seems a waste to use anything larger
While tweaking all the nifty dohickies within ethminer and the GPU settings to maximize output, I have crashed the systems more than a few times looking for the maximum hash output. What I have found is that when the systems crash data is left behind on the hard drive which will eventually fill up the hard drive and give me the "There is no more space available on the hard drive" error.
I did manage to delete some (whatever they are) files in the .ethash folder within the HOME holder. I'm assuming these are DAG files that were not removed when shutting down correctly due to crashing. When I would empty that .ethash folder, Ethminer would run again and wind up loading a new DAG.
HOWEVER, the hard drive still seems abnormally full, so I'm assuming there is other data being stored elsewhere that is getting abandoned due to the previous crashes.
QUESTION #1 Is there a way to clean up the abandoned / orphaned files from ethminer when the system would crash and leave it behind?
QUESTION #2 I've been using ctrl-c to end the ethminer program. Is that the approprite way to shut down ethminer, or is there a specific command to properly shut down ethminer?
QUESTION #3 When I would crash the systems, the video output freezes. Since I cannot see what I'm doing anymore, I have to use the power button or the reset button to reboot. Is there anything I can do to try to get that video back so I can properly shutdown and reboot?