mprime under Mint wasn't working -- had to switch to Lubuntu
A while back, I asked for suggestions on Linux distros/flavors: http://www.democraticunderground.com/10971057
Based on that feedback, I've tried out a few (for small values of few) and was mostly happy with Linux Mint/Cinnamon. Unfortunately, the one program I run most (mprime, from the GIMPS project (http://mersenne.org) ) has some problems with Mint, which only became apparent recently. I maxed out the RAM on these two computers to 8GB for the specific purpose of doing P-1 factorizations, which need lots of RAM. Then when I started actually running P-1 jobs it seemed the HD indicator LED came on so frequently it seemed to indicate lots of VM use -- definitely not something you want on a big numerical job. The interface slowed to a crawl as well.
Fortunately, I had formatted this disk into three partitions, so I could try another distro without too much sacrifice. I had installed Lubuntu 14.04 on the second partition and forgotten about it :\ but when I tried to boot from it the mouse wouldn't work. Tried reinstalling from the CD with Internet upgrade and got an error message -- some applications could not be restored -- and mouse still wouldn't work. Finally erased the partition and installed 14.10 from DVD (just a few MB too large for CD 
) and everything works fine now. Lubuntu has some features I find kind of strange but they seem to be things I don't need to use so no worries. Most of the time this machine runs headless so the interface isn't that big of a deal. The option "launch terminal from this folder" is exactly the kind of thing I've always thought should be part of a GUI over UNIX ever since Apple's first release of OSX; Lubuntu gave it to me (finally!). Unfortunately, the equally enticing "launch process from this folder" (or maybe it was "execute command from this folder"
got me into trouble -- launched a process which I couldn't interact with because there was no terminal window for its output. Then I found I couldn't kill that process even with sudo, and ended up having to reboot. **Other than that**, things seem to be fine now and mprime is doing my P-1 jobs without all the disk thrashing, and completing them in less time. The interface is still pretty impaired, but for this special-purpose computer, that's not such a big deal. For now, I'm leaving the other computer running Mint, and just not doing P-1 jobs as the default.
Anything else I can do to minimize RAM usage ? I have a copy of Puppy Linux, and might give that a shot, just to see if there's further improvement.
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