Light profile


Spending some serious time thinking about this because it makes a difference for the efficacy of the light.

In this revision I basically try to get “cone shape” spectrum. Meaning I have more red at the center of the cone and more blue at the edges, and the peak circle right around the cone top.

I had to make the design decision to not put the main effort into the ease of wiring but into the efficacy because it is more important. What this basically means is that there will be 6 different supplies going for each vertical row. I will probably run bus bars at the top/bottom and use the heatsink as common ground. Should provide nice low-impedance path.

I also toyed with the idea of wiring the lights in series but a) that isn’t necessarily good practice when it comes to leds, and it would create more complicated power supply design and my gut feeling is that it would be more trouble than anything else.


This is the idea of the light; to have control over multiple different spectrums all in software.

High blue

This needs more blue in the middle.


Balanced red

I call this balanced because it still has the Full Spectrum element in it, with high peak on blue, but with wide red.


High red

This pattern I am pretty happy with. It has strong balanced red across the space.


Fixes to spectrum

After seeing thos pictures above I made the following changes to high blue:


It is only 9W more super cool at the middle but visually it gives more balanced look. There is the full spectrum at the middle but it has the strong red element in it.


Virsh: mount new cdrom live

virsh # qemu-monitor-command mirage --hmp --cmd "info block"
drive-virtio-disk0: type=hd removable=0 file=/home/daoist/mirage/mirage.qcow2 ro=0 drv=raw encrypted=0
drive-ide0-0-0: type=cdrom removable=1 locked=0 file=/home/daoist/iso/en_windows_7_ultimate_with_sp1_x64_dvd_u_677332.iso ro=1 drv=raw encrypted=0
virsh # qemu-monitor-command mirage --hmp --cmd "eject drive-ide0-0-0"
virsh # qemu-monitor-command mirage --hmp --cmd "change drive-ide0-0-0 /path/to/new.iso"

QEMU-KVM Installing Windows 10 Client

Pretty powerful tool

Infrastracture change officially done

Final touch

Got the riser card today and got the SCSI controller installed in matter of minutes with no problems at all, and that means that I now have − let me calculate − 26.4TB of tape and about 1.5TB hard drive to store all my data on.

Or actually about 13TB of tape because I do everything in double but nevertheless, all this should be good for at least 5 years.

Looking forwards for new projects. Got some in the pipeline but those are work related and cannot really talk about them except on very high level.

Except the upgrade to 12 cores and 64GB of memory. Running a bit low on memory with 12 guests.

Toshiba MQ01ABB200 quick review

  • Bit slow (70-80MiB/s read)
  • Mini cache (8MiB)
  • No S.M.A.R.T

But the price is correct and excellent value for price for simple storage application without any particular speed requirements. 9/10 for the value in 2.5″ market segment.

Also, Toshiba is a quality disk manufacturer so expect long life. Bit error rate is the standard 1 in 1014 and very low energy consumption of max. 1.7W

Toshiba MQ01ABB200

Got the disks today and they seem to be as dummy as they come: smartmontools reports them 15kRPM, which they aren’t, plus, they don’t have any S.M.A.R.T. capabilities.

So they have saved cost on using some cheaper controller or dropping everything “unnecessary”. Cache size also severely limited at 8MiB.

But none of this bothers me because the disks are a) Toshiba and b) cheap, and I run intelligent filesystem on top of them so cache size doesn’t really matter, and these are for rarely accessed data storage so none of the disadvantages really matter.

And they are Toshiba disks. And especially meant for storage applications. So I am happy with these disks as long as they give me reasonable performance.

I will move all the rest of the data on these two disks and wait for the riser card to arrive, and then dump most of the data onto tape and hopefully be done with this mess for couple of years.

Visual on energy savings


Before the change the consumption was about 1,20kW 24/7 and 365 days a year, and now it seem to be about 0,40kW. That spike at the end is when I for a short period turned on the two old servers. So about 66% reduction in electricity bill. And because my consumption has been about 10 000kWh a year at about 0,11€ per kWh, the cost reduction will be 0.66*10000kWh*0.11€/kWh ≅ 726 €.

That’s a hell of a saving! That is a big chunk of net income! Will pay large portion of car insurance.

rclone and Backblaze B2 for $0.005/GB storage

After long seek, the combination of rclone, Borg Backup and Backblaze B2 (obviously) turned out to be the best choice.

Borg Backup takes backups every 2 hours and rclone syncs the backups to Backblaze. Other alternatives such as B2_Fuse couldn’t be used because they were “too simple”, and required either trusting that the data got stored properly or required downloading the data which is out of the question because that costs a lot.

But rclone seems to be a quality product. It has yet to give me any error messages, something what B2_Fuse was very good at. Bad thing is that there is no way of verifying that the backup works because it would cost. But that is due to design of Backblaze B2, and not because of rclone or any other application using Backblaze.

Borg Backup is currently single threaded which is sort of a problem because G3 Opterons are not fast enough to handle everything in single thread. But there is a new version in the pipeline which should rectify that, I hear.

Other than that, Borg Backup is an excellent product! It does deduplication which enables me to take frequent backups. A dozen of virtualized Linux machines only adds about 200MB per 2 hours.

Backblaze has really done good job getting the price this low. I was previously a long-teeth’d fan of Amazon Glacier, because it was extremely cumbersome to use, but offered the best price for storage. Backblaze B2 response time is practically less than 2 seconds, whereas Amazon Glacier is about 4 hours. So using Backblaze is nice experience, whereas Amazon Glacier can be like talking to New Horizon, beyond the planet Pluto.. New Horizons, New Horizons, can you hear me, can you hear me? Earth, Listening.

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