Category: Uncategorized

Now that I have my ZFS filesystem spanning several drives in place on my Z440, I wanted to get an idea of how this setup is performing together with the underlying LUKS encryption. And while I am at it, the other questions I had in mind were: How does this compare to the ext4/LUKS combination I use on my notebook and how does the write performance look like from inside a virtual machine running on my Z440. A lot of obvious results but also quite a number of surprises.

Continue reading SSD, ZFS and VM performance – Workstation Power At Home – Part 12

This is a quick follow-up post to the previous one in which I’ve written about how straight forward it is to use ZFS to combine several physical SSDs or disk drives to use the combined capacity for a file system. The one thing I left out in the description was how to encrypt the setup. While ZFS encryption is said to have a good performance starting with version 0.8.4, Ubuntu 20.04 I use at the time of writing is still using 0.8.3. The advice of ‘the Internet’ is thus to use LUKS as an encryption layer below ZFS.

Continue reading ZFS with LUKS – Workstation Power At Home – Part 11

In previous parts of this series I’ve been looking at CPU power, GPU power, virtualization, remote graphical GUIs and networking of my refurbished Z440 workstation. The next thing on my list of things I wanted to improve in my computing setup was storage.

So far, I was mostly using ext4 filesystems on partitions on physical disks. This has served me well over many years, it’s a straight forward approach and disk drives were usually bigger than the amount of space I required. On the workstation, however, this would have been limiting as I had two spare 2 TB SSDs that I wanted to combine to get a filesystem on which I could store up to 4 TB of data. Also, I wanted to have the possibility to extend this later. I discounted spinning disks with much higher capacity (for the moment), which could also have solved my storage problem, as the workstation is below the desk and I wanted to have a quiet system.

Continue reading ZFS for Storage – A Primer – Workstation Power At Home – Part 10

After the both good and bad performance of my Lenovo X250 and Ubuntu 20.04 over a 2.5GbE link to my workstation, I couldn’t just leave the topic but had to further investigate how I could potentially improve throughput when using Ubuntu’s Nautilus file manager to transfer files to and from the workstation. And again, some surprises waited for me.

Continue reading 2.5GbE Performance Revisited – Workstation Power At Home – Part 9

I’m quite amazed I am already into part 8 in this series of exploring the limits of using a headless workstation as a ‘power booster’ next to my notebook. The next thing I have taken a closer look at is the connection between the notebook and the workstation, a 1 Gbit/s Ethernet link. That’s good enough for just about anything I want to do except when transferring large files. And mind you, when I say large, I don’t mean a couple of 100 MBs or even a gigabyte, that just works fine over such a link. But when transferring, say 100 GB, it does become a bottleneck. So something faster is necessary. How hard can it be, I thought, and was quite surprised by the answer.

Continue reading 2.5GbE Network Performance – Workstation Power at Home – Part 8

It’s a bit of a strange headline perhaps but my recent blog posts on working with a headless workstation that supplies extra CPU muscle to my working setup has a lot to do with the envisaged 5G evolution of wireless networks and services. Let me explain…

Continue reading 5G and My Headless Workstation

In two previous posts I wrote about how to use RDP and VNC to access the graphical desktops of the virtual machines on my headless workstation. Both have in common that the desktop of the remote virtual machine is put into a window on my client machine. That is great for many purposes and when used at the resolution of the screen connected to my client machine in full screen mode, it is almost like working directly on that machine. Also, the whole desktop with all applications running on it can just be ‘minimized’ to the dock when not needed for a while. For Linux virtual machines, there’s a third option that is even cooler for some use cases: Remote X over SSH!

Continue reading Remote Visual Computing – Remote X over SSH – Workstation Power At Home – Part 7

Once upon a time web pages were simple enough to save them locally for reference or future lookup with the browser’s built-in tools. And to just preserve how the web page looks, ‘print to PDF’ was my first choice. The problem with printing to PDF these days is, however, that the browser tries to format the web page for A4/letter format, which often destroys the layout of the page. In many cases, parts of the web page are missing or horribly distorted, and content is cut between A4/letter pages. Pretty much unusable. But have you noticed that Firefox has a handy ‘screenshot utility’ that does the job perfectly?

Continue reading Tip of the Day – Firefox Screenshot Utility

In the previous episode I’ve described how to use the Remmina remote desktop client in combination with the Virtualbox RDP remote screen capabilities to graphically interact with my virtual machines on my headless workstation server. While this works great it has two disadvantages: RDP requires a lot of bandwidth in combination with low latency. This means that it does not work well over the Internet, even over a 100/40 Mbit/s (dl/ul) link. The other issue is that Remmina’s remote clipboard function in combination with RDP, Virtualbox and Ubuntu 20.04 sometimes freezes the connection for 5 to 10 seconds, which hinders me quite a bit even for local use. So perhaps VNC can be used to work around the two issues?

Continue reading Remote Visual Computing with VNC – Workstation Power At Home – Part 6

In addition to running computing intensive applications on my new (refurbished) HP Z440 workstation the other main use case for me is to offload the virtual machines I am running on my notebook today. While I do have 16 GB of RAM in my notebook it becomes more and more difficult to run two virtual machines at the same time. Memory requirements are growing and particularly Windows starts doing all sorts of things in the background when it thinks it is ‘unused’ for some time, which is a heavy toll on CPU load, power consumption and speed while I’m working on the host system. Also, I do have some applications I run in a virtual machine which are heavily single threaded and some graphical functions are relatively sluggish on a 5 year old mobile processor. So more often than not these days, I only run one virtual machine at a time and in the case of the Windows VM, I pause it whenever I don’t use it so Windows doesn’t run wild with background tasks. Long story short, the idea with the workstation is to run those VMs on that machine and to remotely access their ‘virtual’ screens over the network. Added benefit: With 32 GB of RAM on the workstation, I can be much more generous with assigning RAM to the VMs than on the notebook.

Continue reading Remote Visual Computing with RDP – Workstation Power At Home – Part 5