Dabbling with virtual machines

The software I’m using to do some of the Monte Carlo simulations (PCXMC) for my PhD research is Windows based (fortunately it runs without any issues under Wine) and single-threaded, which makes some of the larger simulation sets I’m doing extremely inefficient when running them on my computer. The PCXMC window would also pop up every 5 minutes or so when another simulation started up and interrupt whatever I was trying to do at the time. It was tolerable since the smaller sets only took a few hours to complete, but I decided I was going to need a better solution.

One solution I attempted was to try running multiple instances of PCXMC, but they ended up clobbering each other and was just ugly.

The next obvious solution was to run PCXMC in a virtual machine (VM). Until now, I haven’t had much need to learn much about creating and managing VMs but they seem like a perfect solution to the problem. I can spin up a few VMs to run PCXMC and have each of them run different parts of the larger simulation sets or different simulation sets.

Virtual Machine Manager , I’ve discovered, is a super handy utility that makes creating and keeping track of VMs super easy. It offers a nice intuitive GUI interface for creating and managing VMs. I can use a live ISO image of my choice to create a new VM with the amount of RAM, storage, and number of CPUs needed. Once I’ve got a VM set up and configured with everything it needs, it’s easy to clone however many copies of the VM that will reasonably fit into my hardware.

Virtual Machine Manger window
Virtual Machine Manager window

The first VM I created had 500 GB of storage, 8GB of RAM, and 2 CPUs. Created a few more with only 250 GB of storage, 8GB of RAM and 1 CPU. Put four of these to work on one of the larger simulation sets over the weekend. The first time I ran a version of the set, it took about 10 days to finish on my computer. With 4 VMs each running a different part of the simulation set, everything was finished in about 2.5 days. Sweet. I can peek in on each VM with a viewer application to see how each one is running, but otherwise they run quietly and hidden away on their own. No more PCXMC windows popping up on my desktop to interrupt me while I’m doing other things.

Quickly realized that these VMs were way more than was needed, and 4 VMs with 8 GB of RAM each didn’t leave my computer with much memory left for doing much else (it only has 24 GB RAM). Next task will be to create some VMs with one of the other lighter Fedora spins (LXQT maybe) and a smaller footprint (100 GB storage, 4 GB RAM) to run PCXMC with.

Computer upgrades

The computer got another hard drive upgrade when the 1TB drive holding my home directory started throwing errors and disappearing from the system. After causing a small amount of panic and a few reboots, the drive managed to stay stable enough for me to get it backed up to the LVM partition. Now it’s been replaced with a 1TB SSD which has given me a nice speed boost.

The nearly 10 year old mid-range (at the time) video card, a GTX 260, also got an upgrade to a much newer and higher end GTX 1660 Ti. The GTX 260 was getting pretty old, and I was starting to get some weird errors with the nouveau driver, so I figured it was time for an upgrade. The new card is about 2/3 the length of the GTX 260, which gives a little more room around the SATA ports and hard drives to work. Hopefully I’ll be able to put the GPU to some number crunching work at some point, and later maybe get into a bit of gaming (after the PhD of course).

Hard drive upgrades

One of the hard drives in my computer had been spitting out errors for a little while now, so over the weekend I revamped the storage in my computer. I’m also expecting the simulation work I’ll be doing for my PhD will require a decent amount of storage, so I picked up a couple 4 TB WD Blue hard drives from Newegg. They were a decent price, and brought my computer from a total of about 3 TB up to just over 10 TB of storage.

The failing drive (1 TB) got replaced, and I also took out an old 250 GB IDE drive that I was using as a place to temporarily dump files. That left a 1 TB drive, two 500 GB drives, and the 250 GB SSD.

After doing a bit of cable gymnastics in the case, the two new drives got installed and plugged in. Current configuration now has the SSD as the boot drive and root partition. I made the 1 TB drive my home directory, and decided to lump the 4 TB and 500 GB drives into a single LVM2 volume group for my primary storage. I considered a RAID 1 or 10 configuration, but with time and brain space constraints, a JBOD setup seemed like it would be easier. I might change my mind later on though.

If it turns out I need even more storage, the case still has one empty drive bay that I stick another drive into.

CPU transplant successful!

The Xeon W3690 transplant was a success!