Last fall, I had to start running a pure 64 bit OS as the native OS on my pcs, and Debian 7.6 live, adapted in a "Knoppix" way and remastered several times, has served me very well. But, typically for the pure-Debian bunch, so much was changed wrt live booting and persistence in Debian 8.0.0 that I gave up upgrading. Furthermore, Oracle XE 11g has not survived the remasterings, and I have for now given up on making it work again. (It once did.)
So I am in a sort of squeeze for the moment, not being able to upgrade the OS, and without a working Oracle version. But VMware Workstation 10 works very well, and I have turned to running Knoppix 7.X in virtual machines to solve the problems coused by the native OS version. Once installed, that works extremely well. There are a few inherent problems, though. To avoid them, use Ryumbekes adapted miniroots (see threads in News), and create a new ISO image after remastering. There may also be problems increasing the persistent store, so I strongly suggest that to be set at 6+ GB from the beginning.
Even though it should in principle be possible, I have not been able to run with 64 bits kernel in VMs - but for this kind of use, it's not really all-important: Computationally heavy tasks are of course run natively.
I'm running a typical development system in Knoppix 7.X VM, with Oracle XE 10g, Eclipse EE, JBoss/Tomcat, Maven etc. It is in fact quite similar to Windows virtual machines (VDIs) we use for the same purpose at work, only much better, faster and more versatile. So whenever I can, I work in Knoppix. With just 8-10 GB total size, it's also very handy to take around, fits "everywhere" nowadays. And it's easy to make different variants to cater for different versions of components and tools.
With the upcoming Knoppix release, I will try to create a VM as soon as possible, and probably use that for a lot of daily tasks - instead of taking the trouble to upgrade the "native" OS. (No more ordinary hard disk installs for me, just live versions with persistent store.)
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