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Linus Torvalds
Works at Linux Foundation
Attended University of Helsinki
Lives in Portland, OR


Linus Torvalds

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I got my 23andme report back.

I was kind of hoping for something interesting, but I guess this is one of those "it's better when it's boring" things. No interesting genetic disorders.

But now I know that I have blue eyes and very low chance of unibrow. Whew. All those mirrors weren't lying to me all those years, and it's not my wife sneakily plucking my brow while I'm asleep.

I'm also apparently 99.7% European, and likely to drink more coffee than average. Yeah, that didn't come as a big shock either.
J.O. Aho's profile photoNorman Yarvin's profile photoThomas Galland's profile photoMonchi Abbad's profile photo
Too bad no south pole origins story in there..
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So I wonder what the excuse is from the apologists that think we don't need ECC in the consumer space this time around?

If you are selling CPUs, and you "differentiate" your products around ECC, you should be ashamed of yourself.  It's not acceptable.

Yeah, I've complained about lack of ECC for over a decade now (you know who you are). There's always some f*cking excuse for why some SKU or other doesn't really "need" it.

Stop it with the excuses already. 
New research finds "bitflipping" attacks may pose more risk than many admit.
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I should also mention that DDR3 non-ECC SO-DIMMs and DDR3 ECC SO-DIMMs have different pinouts! Fortunately this is fixed in DDR4.
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Is "walking like a penguin" a good or bad thing?

The Trump quotes keep on coming in the 2016 Republican presidential primaries. Most of them are pretty clearly derogatory ("stupid" or "like a little baby"), but the most recent one where Romney apparently walks like a penguin struck me as pretty ambiguous.

But maybe it's just me that likes penguins. 

Or maybe Trump is a penguin fan too, and trying to cozy up to Romney.  He's done odder things. 

I'm enjoying the Republican discussions more than I would have ever expected.
King Yan Kwan's profile photoKarim Hosein's profile photoDavid Megginson's profile photo
+Karim Hosein​: I thought this was an interesting and (mostly) civil discussion, which speaks well for the people who follow +Linus Torvalds​. I'm always up for a friendly conversation, political or otherwise, and it seems that many others are, too.

That said, sometimes the topics of even civil discussions don't interest me, so I leave quietly—no shame in that, if US politics isn't your thing.
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The android mobile version of Subsurface is currently mostly about being able to visualize your dives (think of it like taking your logbook with you on your phone or tablet - perhaps to show the dive shop, perhaps to look up what the conditions were last time), but even in that limited form it is quite useful.
Subsurface-mobile for Android -- first beta

The Subsurface developer team is thrilled to announce the first beta release of our mobile app for Android.

Subsurface-mobile connects to your Subsurface cloud storage account and allows you to access your dive list from your mobile device. You can scroll through your dives, look at dive details and dive profiles, edit dives, even add new dives on your phone or tablet. After an initial sync Subsurface-mobile works offline, so no worries about being on a dive boat and not able to connect to the network - the data will be synced at the next opportunity when you are back within signal range.

Subsurface-mobile also includes the GPS tracking functionality of the old Subsurface companion app which allows you to collect precise GPS fixes for your dive sites.

At this point Subsurface-mobile will be most useful when used together with the existing Subsurface desktop application. Most notably, downloading dives from your dive computer is so far not possible from Subsurface-mobile (but that is on our to-do list for at least some classes of dive computers).

In order to try Subsurface mobile on your Android device simply opt in at this link:

And don't forget to take a look at the user manual
For this BETA release it is critical that users report any problems with the use of the mobile software. After all, one of the objectives of a beta release is to distribute the software to a broader circle of users using different Android devices and configurations in order to iron out any bugs, ...
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Armando Montes De Oca's profile photoDirk Hohndel's profile photoCyrille Pontvieux's profile photoThomas Pfeiffer's profile photo
+Dirk Hohndel Good point. Maybe once Subsurface-mobile is at a point of maturity where it can be reasonably easily built from source, you might give it a try.
F-Froid's policy makes sense to me, though. compiling from source themselves is the only way for them to make 100% sure that what they ship is what could see the source code for.
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I've been crawling around in our crawlspace for the last week or so, trying to clean up our networking. I long ago bought a structured media enclosure for the crawlspace that is right next to the access door, but it hasn't really seen active use apart from the coax cable junction.

Until this week. When I decided to actually terminate the network cabling at a proper punch-down patch board, and actually mount the network switch properly in the cabinet rather than have it randomly dangling from all the cables.

I'm a horrible network engineer, so when things go wrong, I just assume I wired something badly. But it turns out that just because I suck at wiring, doesn't necessarily mean that somebody else doesn't suck even more. So far I've had three disasters while redoing the networking, but none of them actually turned out to be due to me wiring things wrong.

First I tried to figure out why one of my UniFi AC access points simply would not connect at gigabit speeds. It would show up as "Connected (100 FDX)" in the UniFi control applet, and I just couldn't figure out why.

Now, it doesn't really matter - the 100Mbps connection to the AP is perfectly fine, but it just annoyed the hell out of me that my newly done cable to the mudroom ceiling would be limited to 100Mb speeds. 

It turns out that what looked like 100% identical PoE injectors weren't. The cabling was fine, but one of the AC Lite AP's had come with a GP-A240-050 adapter, while the other one was a GP-A240-050G. That "G" was what made one connect at gigabit speeds while the other didn't.

While debugging that, I noticed that my office only connected at 100Mbps too. No PoE adapter there, but I had changed that cable to come in through a punch-down patch board too, so I re-did the punch-down because clearly I must have screwed up. No change.

It turns out that apparently I had never connected at gigabit speeds in the first place, because the cable from the wall to the switch in my office was to blame. And it wasn't even one of the cables I had made myself, so it was just about the last thing I decided to test.

And yesterday, I cleaned up the closet where all this crawlspace activity actually comes out to the cable modem, and in the process our phone stopped working. I haven't done phone wiring before, but how the hell could I screw up a single pair? That takes a special kind of skill - the "short bus" kind of special.

Our crawlspace phone wiring is a huge mess, with an ungodly mix of the old-style black-red-green-yellow wiring, and more modern CAT5/UTP wiring. I'm used to the 568A/B confusion, but have never really done BRGY before, so I checked and re-checked my connections and couldn't find the problem.

In the end, I knew everything but the new keystone jack had worked at an earlier point, and I just decided that the punch-down must have failed. That RJ25 jack really looked questionable anyway, not at all like the quality RJ45 jacks I'm used to from doing networking.

So I went to Home Depot and got a new jack with proper color-coded punch downs around the sides, and now our phone works again.

So now everything works, the closet that has our cable modems looks clean and has a proper shelf for the modems rather than having them hanging by the cables coming out of the wall, and I'm mostly happy.

Except now that I've done the telephone cable thing, and have a proper punch down panel in the media enclosure, I have a hankering for fixing the phone cables in the crawlspace too.

Because right now all the phone jacks connect to where the phone company used to bring in the wire probably 20 years ago, way in the back of the crawl. And I could instead just get it to all connect in that proper panel that I now have...

I'm just not sure how much more time I want to spend in that crawl space. Even if it would be for a good cause.
Linus Torvalds's profile photoJohan Heikkilä's profile photoMarkus Ingalsuo's profile photoAaro Koskinen's profile photo
+Johan Heikkilä You can even run mainline Linux on EdgeRouter Lite, though not all acceleration features are yet available. (Ubiquiti firmware handles routing with proprietary binary-only kernel modules.) Also USB and ethernet drivers are still in staging due to lack of active developers. :-/
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So, completely hypothetical question... 

Let's say that you were less than gifted, and had a UniFi AC Lite AP that you hadn't mounted in the ceiling because you're really lazy and didn't have your house wired to the right location.

But rather than attach the mounting plate to the back of the AP to keep track of it, you'd misplace it and probably throw it away.. Because, as mentioned, you're about as stupid as a doorknob.

Now, let's further imagine that you finally did the whole crawlspace and attic thing to get a cable where you wanted it to go.

How would you now mount it, having lost the mounting hardware?

This is all entirely hypothetical, of course. I wouldn't do something that stupid. I'm just asking for a good friend.

Edit: sticky velcro it is. Looks very professional, not at all like it was done by some birdbrained yokel. Thanks, people.
Jason Jespersen's profile photoBarry Flanagan's profile photoGabriel Rossetti's profile photoVee Grig's profile photo
aha - a friend? a diving buddy i bet. :-)
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I'm enjoying the Youtube mixup of the SpaceX CRS-8 first stage landing with Lonely Island's "I'm on a boat" song. Congrats to everybody involved.

I'm not very hip, so the only other time I've heard that song is when somebody in my poker group is mangling it (horribly). I think it works better for Elon Musk, but maybe that is because I'm not losing money.
Daniel Kolm's profile photoJackie Moon's profile photoNilesh Kokane's profile photoArinerron -'s profile photo
+Linus Torvalds​ You probably have hundreds of notifications each day, so I'm curious-- do you actually check them? :)
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Hey, I have a new math problem for G+ people.  This worked really well back a few years ago when I did the "figure out number of bytes from a bitmask efficiently", so let's see if somebody on G+ has the background to do a good job on a totally different math problem for a totally different open-source project.

This time, it's about gas compressibility in scuba diving, obviously for the +Subsurface project.

The issue is that scuba cylinders end up having a (small) gas compressibility factor difference from the ideal gas law, and it's noticeable enough that some people care.

For example, one of the most common cylinders, the AL80, fits 80 cubic feet of an ideal gas, but only about 77.4 cubic feet of actual air, because air at 3000 psi (the fill pressure of an AL80) has a "compressibility Z factor" of about 1.03.

And it turns out that there are many ways to get those compressibility factors, but they all have some problems.

 (a) ignore them. That's actually quite reasonable, but at higher pressures - but still relevant to scuba - the 3% error ends up being more like 10%.

 (b) use a table lookup. That's what we did for a while, and it works fine, for air. Take the air compressibility table at 300K from Wikipedia, do linear interpolation between points for pressure, and you get quite good results. But only for air.

 (c) use actual functions used by physicists. This is the next step we did, because one of the people involved is an actual physicist. The idea is that you can get the compressibility right for other gases too. Sadly, the common functions actually do pretty badly for the usual scuba gases and pressure ranges, probably because these are not ranges that most physicists care about.

 (d) use a least-square polynomial fit of the Wikipedia values. This gets you much prettier code, and good approximations, but gets us back to "just air", but at least in a prettier form than my disgusting table lookup.

 (e) something else.

My current idea for (e) is to do the same least-square fitting for the three relevant gases (Oxygen, Nitrogen and Helium) using the table at

and then just doing a linear interpolation of the compressibility of the different gases based on the actual gas mix.

Anyway, I realize this is pretty esoteric, but maybe there is somebody around on G+ that can tell whether that linear mix is a good idea or just horrible. 

Don't tell me about van der Waals equations or Redlich-Kwong. Our resident physicist already tried those. In the range we care about (temperature at about 20°C, pressure in the 1-350 bar range), they aren't actually sufficiently close to the experimental values to work..
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+Linus Torvalds​ Thank you for making my life so much better by developing Linux, fellow Oregonian. I remember you saying respect is only earned. Well, you have definately earned my respect! :)
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Went to the Bay Area for Daniela's gym meet over the weekend, and watched the local evening news on Saturday.

I'm convinced the discussion in the newsroom before their weather segment went something like this:

 "Should we kick some puppies onstage tonight?"

 "No, we did that last weekend. How do you feel about pentagrams and human sacrifice?"

 "Wait, I know - there are people from Portland in town. How about we make the whole weather segment be about how we're finally getting some much-needed rain? Let's look extra happy about it!"

 "Mwhahahahhhahh! Perfect!"

... and then they went on to do exactly that.

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+Linus Torvalds Sir, don't have enough words in any Language :-|
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I'm looking at the Google Play Music family plan, because I'd like to make sure the kids end up listening to their music legally. 

However, that thing must be the absolutely worst documented thing ever. Either that, or it's the most mis-designed thing ever. So before I take that plunge, can somebody who uses it clarify which of the two it is, by answering this simple question for me:

Q: Can I actually sign up for the family plan (what $14.99/mo), without having to then worry about any mistaken purchases by the kids.

Don't get me wrong - it's no that I don't trust my kids (or my wife, heh) to behave. But every time I look at the FAQ for that thing, I end up struck by the fact that the whole "family payment plan" seems to be tragically misdesigned, and is a "family can randomly use the credit card information you put in" plan.

Yes, in-app purchases are restricted, but that seems to be the only thing. 

Maybe it's just the support pages that are garbage.  I can hardly complain about that, considering how much great documentation I write myself.

So please tell me it's just the docs that are crazy.

Because I can't imagine that anybody would be so stupid as to actually design a system the way it's documented.

I take that back. I can imagine that, which is why I'm not signing up without clarification..
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Hey, i use SoundCloud , is music for streaming , really sometimes i don't can found all the songs that i like but. ... the self artist upload the contents (i feel good with it) and is like a social network also ;)
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I just upgraded one of the kids' machines and decided to finally get one of the Intel NUCs (and the small M.2 version at that, because who wants rotational media? Certainly not me).. 

I have hardly even done more than installed things on it, but I'm already a big fan. I've always enjoyed the small desktop form factor, and used to use a Shuttle SFF for my own use and had several Mac Minis back when they were the smallest thing around.

The NUC is just a (much) better modern version of those. Add a M.2 SSD and some DDR4 RAM, and you have a really nice box that really has everything you need.

Ok, so I won't use it as a main desktop (I do want more CPU for my builds), and I'd love to see a version with two ethernet ports (for routing), so it's not like the NUC is ready to replace every box in the house.

But for a basic solid desktop with both reasonable wired and wireless networking and perfectly fine graphics for non-gaming use, it really is a very lovely box.
Explore Intel® NUC Kit NUC6I3SYK, with 6th gen Intel® Core™ i3-6100U processor, 7.1 surround sound, and an M.2 slot for the fastest SSDs available.
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Yap, me I love the single board family 
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Judging by all the "worst company in America" stories, I was probably the only person in the country that didn't use to hate +XFINITY. They hadn't screwed up once.

Until now.

Because of the lack of problems with Internet and TV, about a month ago I switched over voice to them too, since the traditional landline phone service here has had the box at the street flooded pretty much every year, with resulting grounding problems and horrible hiss etc.

Our voice line works fine. But thanks to XFINITY apparently happily selling their number database to scammers, we're now absolutely inundated with scam calls. As in "several times a day".  Microsoft support, IRS, you name it.

Christ-on-a-stick how I hate phone scammers. And now, thanks to being an enabler, I hate your guts too, XFINITY. 
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Visit and sign up.  Deflects all junk calls from Xfinity lines.  Rings once, then forwards to neverneverland.
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Creator of Linux and git
  • University of Helsinki
Basic Information
SW Engineer
  • Linux Foundation
    SW Engineer, present
  • OSDL
  • Transmeta Corp
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Portland, OR
Helsinki, Finland - Bay Area, CA
I've been to Fish 'n fins twice now, once during off-season (June), and once during high season (November). Very professional. They clearly get very crowded during high season, but seem to successfully juggle having multiple boats out. Good diving, good people.
Public - 2 years ago
reviewed 2 years ago
1 review