Because it has to be repeated again and again: We need to drastically reduce the number of cars to solve our problems.

Flent is featured in LWN! 😲🤩
https://lwn.net/Articles/920121/

I'm gonna keep posting this until one of you fucking boosts it

@ljs @joel_linux RCU is simply broken down into three parts:

• grace periods
• quiescent states
• synchronization

A quiescent state is a time or action that guarantees all grace periods that were running at the time of the synchronization have finished (but you do not care about grace periods that started after synchronization).

If a link list protected by disabling preemption, then the grace period is when preemption is disabled, and the quiescent state is when all CPUs have scheduled. So you can remove an item from the link list (where all readers must have preemption disabled to read it), and then wait for all CPUs to schedule which guarantees nothing has access to the item, where you are now free to delete it without worrying that something is reading it.

That’s the simple case. There’s more complex cases, but it all comes down to the three parts above.

@larsmb
I use my reMarkable tablet for that, which I think is of a similar size (and also e-ink)? Works well enough - the text is a bit smaller than it would be in print, but it's legible enough, for me at least :)

Are you someone who has a simple fix for something in the Linux kernel, but haven't bothered submitting a patch because you find the email workflow daunting? Can be a bugfix, spelling correction, anything at all.

If so, I want to talk to you! I have tools that simplify this process quite a bit, but I need more feedback from people who aren't long-term Linux maintainers.

Please reach out, either via here or by emailing mricon@kernel.org.

@lolonurse @molly0xfff yup, that's my plan as well. A friend of mine just got a new puppy, so he gets first pick. Will try to find a good home for anything left after that. I just sorted everything today, in fact, which is how I know there's a whole pile...

@lolonurse @molly0xfff so I've discovered! Marvin has a very generous grandmother (i.e., my mum) who may have gone a little overboard showering him in gifts while he was still growing. So I have a whole pile of stuff that doesn't fit him anymore. 😅 He definitely needs it, though, his fur is not made for winter! Or rain, for that matter...

@molly0xfff dog-sized horse blankets are a thing! You can even get them with proper (synthetic) fur lining for that extra touch of style! 😅

Computer science pioneer and United States Navy rear admiral Grace Hopper was born #OTD in 1906.

As far as I’m aware, she is the only person who has both a supercomputer and a US Navy destroyer named after her.

Image: Computer History Museum

Shared by my Daughter
"I need privacy, not because my actions are questionable, but because your judgement and intentions are"

In response to "if you have nothing to hide you have nothing to fear"

@monsieuricon Seems to be better, yes; thanks! :)

Back in November I did a presentation at the Driving IT conference in Copenhagen, where I tried to make the case that we should all focus more on latency and less on throughput when building systems and applications.

The talk is really channelling Stuart Cheshire's classic rant (from 1996!), from which I also shamelessly stole the title: "It's the Latency, Stupid!"

Anyway, the video is now finally online, if you'd care to have a listen: https://videos.ida.dk/id/1_47l9o3qn

Okay, so let me tell you about my doorbell, from a #networking perspective.

When you push the button by the door, it sends a message over the #zigbee wireless mesh network in my house. It probably goes through a few hops, getting relayed along the way by the various Zigbee light switches and "smart outlets" I have.

Once it makes it to my utility closet, it's received by a Zigbee-to-USB dongle, through a USB hub (a simple tree network) plugged into an SFF PC. From there, it gets fed into zigbee2mqtt, which, as the name implies, publishes it to my local #mqtt broker.

The mqtt broker is in the small #kubernetes cluster of #raspberrypi nodes I run in my utility closet. To get in (via a couple of #ethernet switch hops), it goes through #metallb, which is basically a proxy-ARP type service that advertises the IP address for the mqtt endpoint to the rest of my network, then passes the traffic to the appropriate container via a #linux veth device.

I have #HomeAssistant, running in the same Kubernetes cluster, subscribed to these events. Within Kubernetes, the message goes through the CNI plugin that I use, #flannel. If the message has to pass between hosts, Flannel encapsulates it in VXLAN, so that it can be directed to the correct veth on the destination host.

Because I like #NodeRed for automation tasks more than HomeAssistant, your press of the doorbell takes another hop within the Kubernetes cluster (via a REST call) so that NodeRed can decide whether it's within the time of day I want the doorbell to ring, etc. If we're all good, NodeRed publishes an mqtt message (more VXLANs, veths, etc.)

(Oh and it also sends a notification to my phone, which means another trip through the HomeAssistant container, and leaving my home network involves another soup of acronyms including VLANs, PoE, QoS, PPPoE, NAT or IPv6, DoH, and GPON. And maybe it goes over 5G depending on where my phone is.)

Of course something's got to actually make the "ding dong" sound, and that's another Raspberry Pi that sits on top of my grandmother clock. So to get *there* the message hops through a couple Ethernet switches and my home WiFi, where it gets received by a little custom daemon I wrote that plays the sound via an attached #HiFiBerry board. Oh but wait! We're not quite done with networking, because the sound gets played through PulseAudio, which is done through a UNIX domain socket.

SO ANYWAY, that's why my doorbell rarely works and why you've been standing outside in the snow for five minutes.

@Teri_Kanefield @Teri_Kanefield thanks for the head's up, already found and followed you there :)

(Odd that the automatic move thing didn't work)

Without internet connectivity since yesterday afternoon. Looks like my upstream ISP had a largish equipment failure which took them all night to recover from. This morning I have a physical connection (I get LLDP packets from a device at the other end) but my BGP peer is MIA.

Spent an hour in the helpdesk queue and all they could tell me was "we'll put it in the queue for our technician". Ugh.

Do I know anyone who can provide me with a temporary BGP session over a tunnel (and reannounce my addresses to their upstream)?

@thetitanborn OMG, this, so much! If it's two people arguing about what to do, it's an argument. If it's three or more, it's politics!

Did an interview for a Danish newspaper about #bufferbloat and internet connectivity. The article turned out pretty well, I think! It's in Danish and unfortunately paywalled, but just in case I know anyone with an account, here's the link (article by @LauridsHovgard):

https://ing.dk/artikel/daarlig-koekultur-din-router-flaskehals-din-netforbindelse-263272

@jwildeboer another interesting implication of this is that maybe the reason a planned economy failed in the USSR was not so much that planned economies fundamentally can't work, but simply that they didn't have the computational power to implement it properly.

Which is basically the point made in this book: https://www.penguinrandomhouse.com/books/564287/the-peoples-republic-of-walmart-by-leigh-philips-and-michal-rozworski/

@axboe @brauner oh, neat! And yeah, I was going to use mine (the PiKVM) to connect to my build box, but, well, that rarely crashes so doesn't *really* need it. Nice excuse to buy a new shiny, though!