penguin42 @penguin42@mastodon.org.uk

Another ~30 lines of #python in my #zwave control script for my TRVs; hopefully that'll stop it trying to cook me when the boiler kicks in.
There Eurotronic spirit zwave TRVs seem to have some odd feedback rules when the boiler starts and they suddenly go from being too cold to being too hot but have a plentiful supply of hot water; they don't switch off fully for ages; I'm trying to detect this via zwave and put them in 'off' mode. I'm a bit worried what will happen on a really hot day.

I looked in the Amazon 'Clicks & Mortar' store in Manchester; it's hmm odd - it's rather like the set of markets you get for small makers/companies - just with only about 5 companies in (each with about one person operating it); very bare shop - but without the vibe of a cool shop.

I do love smartereveryday videos; this one on total internal reflection is notable for just how much random stuff he has in his kayak:
https://www.youtube.com/watch?v=pUwVZUOSTvk

#science

My optician is suggesting I try varifocals for the first time and then offers 5 prices basically from cheap to best; they have no definition of the 5 prices except that the more expensive they are the wider field of view they have. You go to another optician and they have their own brands and names and no way to compare them with the 1st optician; neither apparently has any measurement they can give me to *define* the different models. Very odd.

Of using remote test farms, and you ask someone to check a non responding machine only for them to reply with a picture of an empty gap on the shelf.

The graph from the Argentine energy company is scary - 14GW of load just gone in a fraction of time. I bet the story of that outage will be fun.

https://en.wikipedia.org/wiki/Magnetosome is neat - the structures in some bacteria that let them sense a magnetic field
I cam across it following from a quanta article ( https://www.quantamagazine.org/bacterial-organelles-revise-ideas-about-which-came-first-20190612/ ) about the fact that bacteria have a lot of structures.

#science

I just presented my talk on 'fun bugs' to manlug; go read it here http://www.treblig.org/talks/manlug-funbugs.pdf

Finally finished fixing carpet tiles in my bathroom; now I can get back to something hacky. Not having done carpet tiles before, I laid & cut them, got them all fitting & then came back to them to add tape to stop them moving. That's a mistake; when they've been down for a bit they kind of merge into each other & it's difficult to get them back - using a steel ruler to separate the fluff between them as you put them back helps. Now, what to do with a spare roll of double sided carpet tape.

FYI lvmconvert has an odd gotcha.
Imagine you've got a linear lv on a disk (lets say /dev/sda1) and you want to convert it to a RAID on a new pair of disks, you might try:

lvconvert --type raid1 -m 1 myvg/mylv /dev/sdb2 /dev/sdc2

and hope that creates the new raid1 on sdb2 and sdc2 - but it doesn't! It converts to raid1 but using your existing disk and sdb2!
Fix this with lvconvert --replace later; or start the other way and pvmove it to sdb2 and then do the lvconvert.

#linux #lvm

This is pretty neat for something that's not properly understood; the magi c 1.1degree or so angle in #superconducting #graphene.

https://www.quantamagazine.org/whats-the-magic-behind-graphenes-magic-angle-20190528/

#science

318G of stuff rsync'd back into it's (now RAIDd) rightful place. Now lets see if I can delete 100G of it.

<sigh> That drive failed in an odd way. When it hit a bad sector it needed a hard reset, so skipping over the bad sector didn't work. The failed pvmove for some reason restarted and apparently coutned through ticking off data - wth it got data from is unknown since the drive was apparently dead; hmm - anyway that was a screwed partiion. *Initiating rsync beam! Bring my data back! *

arse: failing drive just failed during pvmove

Hmph; today was supposed to be a lovely hot day; hottest of the year they said.... it's 16c at the moment and drizzly. Hmph.