[HN Gopher] Mystery Blips
       ___________________________________________________________________
        
       Mystery Blips
        
       Author : bo0tzz
       Score  : 164 points
       Date   : 2022-11-19 10:28 UTC (1 days ago)
        
 (HTM) web link (mosquitocapital.substack.com)
 (TXT) w3m dump (mosquitocapital.substack.com)
        
       | [deleted]
        
       | IAmGraydon wrote:
       | It's funny - the very first thing I thought while reading this
       | was "check the news". That's probably because I've been involved
       | in markets and when you see this sort of behavior unfold in
       | market price and volume, the first thing you do is check the
       | news.
        
         | MrAwesome wrote:
         | Yeah! By the end of my time on the team, checking the news when
         | I saw a rapid change in traffic was second nature. And later on
         | in my career becoming interested in markets, even more so.
         | Forex in particular - markets with trillions in daily liquidity
         | don't take huge leaps unless something huge happened.
        
       | NKosmatos wrote:
       | Liked the ending of it, nice read :-) Being a data/statistics
       | freak, I would really love to see statistics and usage patterns
       | from big sites or games.
        
       | xyzelement wrote:
       | One of my clients back at a large financial software and data
       | provider, was a southern market making firm.
       | 
       | They kept complaining about "the whole desk being slow" and we
       | spent weeks trying to figure out what was wrong with our
       | software.
       | 
       | Eventually we figured out the whole firm was nuts about golf, and
       | they'd all stream golf tournament to their workstations at the
       | same time and saturate their ISDN or whatever they had.
        
         | steveBK123 wrote:
         | 10+ years ago the networking team at a big European bank I
         | worked for, observed that the biggest usage of network
         | bandwidth on the trading floor desktop network was not the
         | Bloomberg Terminal, market data, or trading application
         | traffic.. but Youtube :-)
        
           | bee_rider wrote:
           | Wouldn't surprise me if YouTube, Spotify, etc were some of
           | the biggest resources users in many offices.
           | 
           | Maybe it would be useful to have a local company radio
           | streaming service, haha.
        
       | js2 wrote:
       | Early in my career, in the late 90s, I was at Cox Interactive
       | Media on the team responsible for the web farm which hosted all
       | of Cox Enterprises news sites: newspapers, radio stations, TV
       | stations. This was before the days of SREs and SROs and dev-ops.
       | We were just system admins and programmers and some of us could
       | do both.
       | 
       | The web farm was about two-dozen Sun Ultra 2s connected on a FDDI
       | loop (we eventually upgraded to GigE), with content on NetApps
       | (4GB drives). A couple Sun E450s. Apache[1] on the Ultra 2s.
       | Apache + mod_perl on the E450s. Hosted at a Global Center DC in
       | Sunnyvale (same DC that early Yahoo was hosted in).
       | 
       | Monitoring with MRTG[2].
       | 
       | It's 1998. The Ken Starr report drops. Now, we knew it was
       | coming, and we did our best to be prepared, but this is the late
       | 90s. There was only so much load testing we could do and didn't
       | really know how much traffic it would drive. We kept the site up,
       | but it meant, as I recall, a lot of fine tuning of the mod_perl
       | box and disabling interactive parts[3] of the site.
       | 
       | I really wish I still had some of the traffic graphs.
       | 
       | Fun times.
       | 
       | [1] Receipt:
       | https://github.com/apache/httpd/blob/1.3.x/src/CHANGES#L5754
       | 
       | [2] Receipt:
       | https://github.com/oetiker/mrtg/blob/master/src/CHANGES#L310...
       | 
       | [3] The forums. OMG forum software was so terrible. I think we
       | eventually wrote our own after nothing based on Netscape
       | Application Server or that we found open source worked well at
       | all.
        
         | daveevad wrote:
         | > same DC that early Yahoo was hosted in
         | 
         | Space Park 1?
         | 
         | Famously, Yahoo wasn't quite up to the task on 9/11 which led
         | to considerable thought about planning for the unexpected 100x
         | event.
        
           | js2 wrote:
           | That doesn't ring any bells. It's been years. I think it was
           | on Borregas Ave and it may have been owned by company called
           | ISI at the time. Equinix has a DC in the approximate area
           | now, not sure if that's the same building and the address
           | changed or my memory is off.
        
       | gooseyard wrote:
       | at the end 1999, my employer hosted what I guess was half NYE
       | Party and half Incident Response. We were optimistic that we
       | wouldn't have issues but figured it'd be wise to have a
       | sufficient crew of designated drivers, so to speak.
       | 
       | Our monitoring system included a mercator projection on some big
       | screens, with colored that showed where our gear was and whose
       | color indicated whether it was down, being hammered, etc.
       | 
       | We had no equipment in UTC+14, so there was an hour of waiting
       | between that zone reaching y2k and when we'd maybe see some
       | action. The control room was mobbed since we also had some
       | televisions running cable news there and everyone wanted to see
       | it.
       | 
       | Despite the anxiety, the gear was looking fine everywhere, until
       | about 5 minutes before midnight in UTC+13, when our locations in
       | New Zealand started to turn red. A hush fell over the room as the
       | operators attempted to open connections to those boxes. The
       | connection attempts appeared to hang, and the party got somber.
       | But after the eternity of a few seconds, we were in. The machines
       | were alive but being hammered; the alerts just indicated the
       | excessive traffic caused by mass numbers of users refreshing NZ
       | based websites as the date change approached, to see whether
       | they'd fallen off the net or not. Breathing resumed.
       | 
       | After 15 minutes or so had passed, the traffic fell off, and by
       | the time y2k reached us in UTC+5 we'd been in full festive mode
       | for hours. I still can't look at New Zealand on a map without
       | seeing it covered in angry red circles, though.
        
         | 2b3a51 wrote:
         | Big street party here in UK on Dec 31 1999. Myself and a few
         | neighbours who thought about these things relaxed a bit after
         | 9pm (Midnight Moscow time) and started partying seriously.
        
       | retrocryptid wrote:
       | Lol. During "high velocity events" at Amazon, we would have a war
       | room with all the engineers and a couple old hands directing
       | responses.
       | 
       | Some of our metrics came in 5 minutes delayed which wasn't a
       | problem for normal days. These metrics moved slow enough that
       | when you got an alarm, there was still plenty of time to take
       | corrective action.
       | 
       | But for HVEs this was an issue. During black Friday or prime day,
       | sometime some metrics spiked so fast you had no time to respond
       | (usually from people hitting page reload a few minutes before a
       | sale kicked off.)
       | 
       | To get an idea for what was going on, I would go in twitter and
       | search for things like "amazon failure" or "amazon 502."
       | 
       | We often got problem reports via Twitter before they showed up on
       | our dashboards.
        
         | MrAwesome wrote:
         | In my time in SRO at FB, we actually had an alarm that would
         | fire whenever enough #facebookisdown posts were made on
         | Twitter!
        
       | xipho wrote:
       | Watch the World Cup be the death of Twitter for this type of
       | thing?!
        
       | tzs wrote:
       | At a place I worked that sold a retail product online we had a
       | weird rate problem that we never were able to figure out.
       | 
       | If you graphed the visit rate to our shopping cart page it would
       | follow a curve that was sort of like a sine wave (well, a sine
       | wave plus a constant because you can't have negative cart
       | traffic) with a 24 hour period. I'm just going to call it a sine
       | wave.
       | 
       | The amplitude varied seasonally, and was different on weekends
       | and weekdays, but generally any given day was a sine wave.
       | 
       | If you graphed order rate it also followed a sine curve too, in
       | phase with the visit curve and generally with a fixed ratio
       | between them. So if the cart was getting N visits per minute,
       | we'd be getting fN order per minute for some number 0 < f < 1,
       | and f was pretty much constant.
       | 
       | This continued as the business grew, so the overall amplitude of
       | the visit curve increased. But at some point the order rate
       | seemed to hit a wall.
       | 
       | What we would then see is that as the visit rate was heading
       | toward its peak for the day when it got to a particular fraction
       | of that peak, say 80% of the peak, the order rate would stop
       | tracking the visit rate and would become flat. It would stay flat
       | as the visits peaked and declined until the visit rate was back
       | down to 80% of its peak and then orders would resume tracking
       | visits.
       | 
       | So far nothing too weird about this. What was weird is that when
       | we'd have a day of especially high cart traffic such as when
       | something in the news caused a big increase in demand for a few
       | days for the kinds of things we sold, and we'd get 3 or 4 (or
       | sometimes even 20 or 30) times the normal cart visit rate
       | throughout the day--the plateau on the order rate would still
       | start when the visit rate hit 80% of the visit rate peak for that
       | day and go away when the visit rate fell back below 80% of peak.
       | 
       | The order processing was handled by a different server than the
       | shopping cart. They did use the same database for product and
       | customer information, but we could not find any signs that the
       | database was a bottleneck.
       | 
       | This just made no sense. Suppose we'd been seeing on normal days
       | that visits would peak at 1000 per minute, and orders were 10% of
       | visits. Then we'd see visits grow from 0 to 800 and orders grow
       | from 0 to 80. Then orders plateaued at 80 while visits continued
       | on to 1000 and back to 800. Then as orders fell from 800 to 0,
       | orders fell in step from 80 to 0.
       | 
       | Now suppose the next day we had 10 times the activity due to some
       | news item. So the next day visits rise from 0 to 10000. The order
       | system would now not plateau until the visit rate got to 8000 and
       | the order rate got to 800.
       | 
       | And then when the increased demand was over in a few days and we
       | were back to 1000 visits peak the order system would again
       | plateau at 80.
       | 
       | So whatever was causing the plateau was somehow tied to the visit
       | rate, making the plateau depend on what the peak visits would be
       | for that day.
       | 
       | But how on a given day when the visits would first rise to 800
       | and the orders to 80...how did it "know" if the day was going to
       | be a 1000 visit peak day or a 10000 visit day so it could "know"
       | if it was time to plateau?
       | 
       | We never figured this out. Reasoning about our systems and their
       | dependencies I could not figure out any way in theory that this
       | could be happening nor could I find anything no matter how much
       | logging and tracking I added all over the place.
       | 
       | Everything I could think of that could even remotely cause a
       | plateau would have caused a fixed plateau, not some weird plateau
       | that's level gets set daily based on what the _future_ peak visit
       | rate is going to be for that day.
        
         | doubleunplussed wrote:
         | If it was really close to the shape on an actual sine wave,
         | then the _derivative_ at any earlier time encodes information
         | about the future peak. Any way some system could be
         | bottlenecked by the rate of change of the visit rate (i.e. the
         | visit acceleration)?
        
       | tonetheman wrote:
       | I did SRE for years.
       | 
       | A lot of time it would end up being DNS or routing somewhere
       | outside of our control.
       | 
       | Sometimes a disk would get close to filling up and a cron would
       | clear it just in time so you would see decreasing performance
       | then it would clear.
       | 
       | Other times we would have a customer that did something that we
       | just did not expect with the system and it would cause SQL
       | queries to slow down in ways we could not imagine. And it was
       | transient so those would be hard to find or explain.
       | 
       | Or we would hit a limit in the load balancer (haproxy) in really
       | odd ways. Too much traffic on the frontend or not enough capacity
       | in the backend. And many other various ways of things not
       | working. Haproxy was and still is amazing software. Really almost
       | magical.
        
         | sbierwagen wrote:
         | >A lot of time it would end up being DNS
         | 
         | Ah, good old "it's always DNS"!
        
       | eb0la wrote:
       | I was working in a Telco that owns a big backbone network in
       | south America.
       | 
       | Our director was very sensitive to traffic changes. Every week or
       | two there was a big meeting at her office to explain what
       | happened when some traffic went down.
       | 
       | That day she was really mad at us. There afternoon before there
       | was 20% less traffic in the backbone and nobody knew where it
       | went.
       | 
       | I was on call that week for the management systems and I was
       | questioned about why the operators didn't have received any
       | alarm.
       | 
       | Turns out Spain was playing soccer against some Latin American
       | team. Spain was our biggest customer. I don't remember if the
       | other team was Argentina, Chile, or Brazil... but it was our 2nd
       | biggest market.
       | 
       | People just decided to watch TV instead of web browsing (that was
       | before mobile phones had an affordable internet connection).
       | 
       | Funny enough eMule traffic spiked during the match. That was the
       | reason I could justify there was no alert in the system for down
       | interfaces.
        
         | userbinator wrote:
         | _Funny enough eMule traffic spiked during the match._
         | 
         | If your bandwidth is limited enough such that background
         | downloading would slow down your browsing significantly, then
         | it would make perfect sense to let the downloads saturate the
         | connection while you watched TV.
        
       | adw wrote:
       | This happens in all infrastructure, particularly power and water;
       | https://en.wikipedia.org/wiki/TV_pickup
        
       | m3047 wrote:
       | I've got a good one. I was working a "tip of the spear" job in
       | threat intelligence (I suppose I was always on call). One of the
       | things we monitored was DNS.
       | 
       | It was always noisy. If it's not the miscreants, its the normal
       | stupidity (DNS is so amazingly survivable of misconfigurations,
       | some of them become folk wisdom; like disabling TCP/53, but I
       | digress).
       | 
       | Othodox Easter Sunday morning. Really really early in the
       | morning, like I can't remember if it was light out yet (US
       | Pacific coast time). The SOC calls me. Nothing is happening.
       | 
       | Nothing is happening. There is no noise. So they've been looking
       | at this, and everything is working. So they called me. At dark-
       | thirty on Sunday morning.
       | 
       | I confirm everything appears to be working correctly. I repeat
       | diagnostics, do ad hoc stress tests, everything. About two hours
       | later the normal crap starts coming back.
       | 
       | We have to conclude that the miscreants, as well as the
       | sysadmins, had taken the morning off.
        
       | ricardobeat wrote:
       | This footnote is almost more interesting than the post itself:
       | > There's a deep beauty to the thought that untold millions
       | of people using the app randomly, but oh so slightly
       | habitually, aggregated together, makes such a predictable pattern
       | 
       | That 'beauty' can be extremely scary from another angle. It's
       | evidence of what makes Facebook, and other social media, such
       | powerful mass manipulation tools.
        
         | euroderf wrote:
         | You just described Hari Seldon's psychohistory.
        
         | retrocryptid wrote:
         | Yes. But just about every big service has marked diurnal and
         | weekly patterns.
        
           | 13of40 wrote:
           | One service I used to work on processed business-to-customer
           | and business-to-business emails almost exclusively, so you
           | could see a recurring weekly pattern, bumps throughout the
           | day when the US east coast, US west coast, Asia, and Europe
           | woke up, and spikes at the top of the hour from automation.
           | So one day we got a new boss, and he called me into his
           | office in a panic so I could explain why his chart of the
           | traffic kept going up and down. Took about four tries, but I
           | think he eventually got it.
           | 
           | I also recall seeing someone push a global update to that
           | system that was packaged wrong, and watching the graph
           | gradually drop and flatline as 20,000 VM hosts across the
           | planet stopped taking traffic. That had its own subtle
           | beauty, in no way diminished by the fact I was just a
           | bystander and couldn't get in trouble for it.
        
         | none_to_remain wrote:
         | I don't see the fright. So many things do this - electricity
         | for example - you turn the lights on and off and run the
         | laundry machine whenever it pleases you, but on the scale of
         | millions of people the power companies predict the daily usage
         | patterns very well.
        
           | ricardobeat wrote:
           | Imagine if the power company could see everything you do at
           | home, and control your lights, laundry machine and other
           | electronics to influence your behavior. They don't have that
           | kind of power, but social networks do.
        
       | encoderer wrote:
       | Maybe it's just the trained operator in me but the whole time
       | he's describing the depressed metrics and blip I'm screaming in
       | my head: it's exogenous! Check the news! He finally gets there.
       | 
       | For us (at normal company scale) I would actually go look at
       | recent activity, new customers, new workloads we are running, but
       | I guess at a Facebook scale it's a lot harder to do that.
        
         | nerdponx wrote:
         | One interesting aspect of the story is that the author was a
         | junior at the time (almost brand new to the job, if I read it
         | correctly), and it was one of the more experienced operators
         | who realized it was exogenous.
         | 
         | in addition to being a good story about the site reliability,
         | it's also a great lesson in the value of collaboration,
         | mentorship, and having senior people around whom you can ask
         | for help!
        
           | MrAwesome wrote:
           | Author here, and that's exactly right! I think it was in my
           | second or third month on the job.
           | 
           | And I really agree with your second point too! Without that
           | in-person transfer of tribal knowledge, it would have taken
           | me ages to learn the ropes well enough to take such a high-
           | pressure high-stakes oncall.
        
       | GauntletWizard wrote:
       | Google didn't have SRO. The closest thing was Traffic Team's
       | oncall; Which was stressful, for sure, and hired some dedicated
       | alcoholics, but it wasn't anything like Facebooks (I knew people
       | on both teams during my time at each). Google had a constant
       | stream of alerts that someone was aware of and handling. Facebook
       | had a constant stream of fire that someone was beating back the
       | flames of.
       | 
       | SRO is madness. SRO is admitting that you're enough underwater
       | and there's enough unexpected critical events to dedicate a team
       | to burn out on it. There was a lot of spend in overcapacity and
       | failover automation testing that kept it that way, and explicit
       | mandates by a C-Suite and VP to keep keeping it that way. More
       | importantly, though, it was baked into the architecture.
       | 
       | Everyone's talking this week about how Twitter will go up in
       | flames in the next few days; I don't think so. I think they're
       | closer to Google in that respect. There's a lot of automation
       | that will keep things alive and a lot of redundancy that will
       | handle the immediate problems of having a lot of the team leave.
       | I actually think the company can continue to run indefinitely if
       | they just follow the operations manuals and replace failed drives
       | and machines. But I think there will be a major outage when they
       | try to launch a new feature and fail.
        
         | MrAwesome wrote:
         | Author here - a few months after the time of this story, we
         | reoriented around a single purpose for the team, "Automate
         | ourselves out of existence". It took a few months to remove all
         | of the dependencies, tag all the alarms, train up all the team-
         | specific oncalls, but we managed to do it, and I had the great
         | honor of taking the very last SRO oncall on March 31, 2014 :)
        
       | prox wrote:
       | I love these kind of stories! Any more HN'ers have these?
        
         | Kiro wrote:
         | The employee shaming on here has scared away all the people
         | with interesting war stories from big companies. Anyone active
         | on HN nowadays probably hasn't worked on anything significant.
        
         | gfv wrote:
         | Pirate video releases generate heaps of traffic, and they won't
         | be on the news. Earthquakes (mild ones, not the "cities
         | collapse" kind) cause people to immediately go online and check
         | on their friends. So do missile strikes, but those tend to
         | generate extremely popular videos as well. During the holy
         | month of Ramadan, you can see a rapid and deep traffic drop in
         | Muslim countries right at their local sunset, when people have
         | iftar, breaking their daily fast. A country in North Africa
         | shuts down their internet access completely during their school
         | exams. Popular web infrastructure sometimes reroutes your
         | requests to distant data centers, leading to request latency
         | exploding together with your queue lengths. In summer, the
         | morning user activity peaks later than in autumn because
         | schools are on their summer breaks.
         | 
         | I bet every seasoned SRE has a few to add.
        
           | prox wrote:
           | So cool to see these things happen!
        
             | jasonwatkinspdx wrote:
             | Here's a fun one I remember seeing a little video on: the
             | UK power authority has to anticipate commercial breaks in
             | major broadcasts like the World Cup because everyone
             | turning on their electric kettle spikes the grid.
        
       | retrocryptid wrote:
       | Another part of my career, I worked on a team that ran an
       | automated content detection service (like YouTube ContentId.)
       | 
       | The database holding signatures for known music samples was
       | sharded by artist. Not as crazy as you might think. You get a
       | trial sample and you send it to all the shards which chunk on it
       | in parallel then you just wait for the servers hosting each shard
       | to respond.
       | 
       | But then Prince died.
       | 
       | The queue for the server that owned the shard Prince was in
       | backed up.
       | 
       | Then our proxy that distributed trials to each shard backed up.
       | 
       | Then our regular reverse proxy backed up.
       | 
       | Then our anemic load balancer fell over.
       | 
       | What we learned for about the bazillioneth time is keep a backup
       | of each shard handy so you can add it into the rotation and pay
       | an intern to watch Facebook looking for news about recently
       | deceased musicians.
        
       | llimos wrote:
       | Once when I was working in a big bank in London during World Cup
       | 2010, they told us all to stream the England games on BBC Online
       | since it would be a good test of their network capacity.
       | 
       | They knew not much work was going to get done either way.
        
       | steveBK123 wrote:
       | Having been at a finance firm trying to implement SRE without
       | SRO, and without staffing either, I do find the story a bit
       | entertaining.
       | 
       | That is - we were mandated to implement all the SRE tooling on
       | top of our apps, with like 1 guy owning the SRE infra, but with
       | no one looking at the charts proactively.
       | 
       | The idea was sold to dev teams that it was something like a black
       | box recorder for the on-call rotation to check first when you got
       | called in the middle of the night/weekend.
       | 
       | In reality it turned into CTO reporting metrics of whether SLOs
       | were being met, lol.
       | 
       | Constantly feel like other industries read like 1/4 of a book
       | about how FAANG does stuff and then adopts the laziest worst
       | implementation of the part they skimmed.
        
         | nerdponx wrote:
         | > Constantly feel like other industries read like 1/4 of a book
         | about how FAANG does stuff and then adopts the laziest worst
         | implementation of the part they skimmed.
         | 
         | I think this is less wrong than you think it is. In the P&C
         | insurance industry, I saw a handful of initiatives that seemed
         | like they were started because a senior manager read about
         | something that sounded cool and high-tech in an industry
         | publication, and/or heard it in a sales pitch from a Microsoft
         | rep, without actually checking to see if it was feasible or
         | even useful.
        
       | jeroenhd wrote:
       | This reminds me of this YouTube video:
       | https://youtu.be/slDAvewWfrA. There's a monitoring room to make
       | sure people are ready to switch backups and reroute in case of
       | some kind of grid failure, but also in very specific scenarios.
       | 
       | Britain being filled with Brits, what would happen is that once
       | the show was over, half the nation got up from the couch to turn
       | on the kettle for a cup of tea. Those electric kettles are quite
       | demanding, especially if millions of them turn on at the same
       | time.
       | 
       | So every time there was a major event, dedicated people are
       | monitoring the grid frequency, power plants on standby and
       | foreign contracts at the ready when needed, just to increase
       | capacity at the right time. You can't just schedule this stuff,
       | because if a football match runs over its allotted time, you may
       | suddenly add power to the grid without any load, causing all
       | kinds of problems like the grid frequency increasing and making
       | digital clocks run ahead. There is a temporary demand of
       | gigawatts of power that rises within five minutes and lasts until
       | the kettles are done.
       | 
       | The YouTube video provides an example of 600MW of power being
       | requested from France... for the end of an episode of Eastenders.
       | 
       | I always knew the British like their tea and that there's some
       | kind of planning going on for events like street lights turning
       | on, but the combination of the two is a great example of complex
       | behaviour that's easy to overlook.
        
         | LeoPanthera wrote:
         | > Britain being filled with Brits, what would happen is that
         | once the show was over, half the nation got up from the couch
         | to turn on the kettle for a cup of tea. Those electric kettles
         | are quite demanding, especially if millions of them turn on at
         | the same time.
         | 
         | Particularly _British_ kettles, which pull 13 amps at 240v =
         | over 3000 watts. A lot more than (standard) American outlets
         | can deliver.
         | 
         | For a while there was a theory going around that this is why
         | Americans typically do not have electric kettles, because they
         | would boil much slower in the USA, but the real answer is that
         | Americans just don't drink much tea.
        
           | dghughes wrote:
           | It amazes me how most of the world is on 240V I'm in Canada
           | and we are like the USA 120V 20A circuits.
           | 
           | Today I made tea and I used a standalone electric kettle
           | which is odd to most of us here in Canada and the US. Most
           | times I would have used the microwave to boil the water. But
           | I used the kettle 120V x 12.5A or 1500W and popped the
           | breaker since the dishwasher was operating and on the same
           | circuit.
           | 
           | In Canada we drink a lot of tea; Red Rose, King Cole and
           | especially south-eastern Canada The Maritimes and Atlantic
           | Canada.
        
             | LeoPanthera wrote:
             | Most US homes actually do receive 240v, it's just done in
             | an unusual biphase configuration with two "hot" phases 180
             | degrees apart. If you connect a device across the phases it
             | will receive the full 240 volts, which is often done for
             | cookers, clothes dryers, and EV chargers.
             | 
             | In theory you could sell a 240 volt electric kettle but
             | your kitchen would have to have a 240 volt outlet, probably
             | a NEMA 6-15. They're not common.
        
               | nraynaud wrote:
               | From watching a bit of YouTube, I think Canada's kitchens
               | have more 220 outlets than American kitchen. They even
               | seemed to have dual outlets with each outlet on a
               | different phase, so all the ingredients are right next to
               | each other to get an outlet un between phases.
        
               | bbarnett wrote:
               | I have never seen a 240V wall outlet, in a house,
               | anywhere in Canada ever. They literally do not exists as
               | a standard.
               | 
               | Not sure why you'd think so, but no.
               | 
               | (ovens and dryers are not wall plugs)
        
               | [deleted]
        
               | ericvsmith wrote:
               | > Most US homes actually do receive 240v, it's just done
               | in an unusual biphase configuration with two "hot" phases
               | 180 degrees apart. If you connect a device across the
               | phases it will receive the full 240 volts, which is often
               | done for cookers, clothes dryers, and EV chargers.
               | 
               | It's technically a single phase with two hot legs and a
               | center tap for neutral, also called "split phase". From
               | the neutral to either leg is 120V, from leg to leg is
               | 240V.
               | 
               | https://en.wikipedia.org/wiki/Split-phase_electric_power
               | 
               | It would technically be possible to have a reverse-Y
               | extension cord that plugged into two outlets and gave you
               | a 240V circuit. The two outlets would have to be on
               | different legs, of course. This is basically what a 240V
               | breaker is doing. I've contemplating wiring up one of
               | these for home and buying a British tea kettle, but the
               | aesthetics got my plan vetoed.
               | 
               | Something like: https://www.nooutage.com/images/adaptor-
               | wye.jpg
        
           | esaym wrote:
           | > For a while there was a theory going around that this is
           | why Americans typically do not have electric kettles, because
           | they would boil much slower in the USA, but the real answer
           | is that Americans just don't drink much tea.
           | 
           | I would drink tea and use an electric kettle if it would boil
           | faster...
        
             | argiopetech wrote:
             | If fast hot water is all that's holding you back, and hot
             | water on standby is an acceptable alternative to freshly
             | boiled, I can highly recommend Zojirushi's line of
             | products. Mine [1] keeps water at my desired temperature in
             | a vacuum insulated canister that uses barely any continuous
             | power. Any time I want coffee/tea/etc., hot water is
             | instantly available. Recovery time after a refill is under
             | 10 minutes on a USA-standard 15A wall socket.
             | 
             | Zojirushi has been in business since 1918 and (in my
             | understanding) is a household name in Japan. Their more
             | expensive (to be blunt) lines are made entirely Japan and
             | replacement parts (like rubber seals, which can wear out
             | over time) are available for purchase through their site. I
             | fully expect mine to last 15-20 years of continuous duty.
             | 
             | Not affiliated, just a thrilled customer.
             | 
             | [1] https://www.zojirushi.com/app/product/cvjac
             | 
             | Edit for additional info: the Zojirushi replaced my Sunbeam
             | Hot Shot single cup boiler that had an unfortunate dry-run
             | and became unusable. They were unavailable in late '21, but
             | appear to be back on the market now. They boil a cup of
             | water in under a minute. If the Zojirushi didn't exist (or
             | I hadn't been willing to bite the bullet on the price) I
             | would buy another in a heartbeat.
             | 
             | Value is what is left when price has been forgotten. Both
             | of these utensils have been high-value for me, but the
             | Sunbeam has a lower initial cost of ownership.
        
             | seesaw wrote:
             | I use an electric kettle to boil water. I got it a while
             | back from Costco. I find it to be faster than our earlier
             | method - using the microwave to boil water.
        
             | jeroenhd wrote:
             | Many American homes receive 240V, with the right wiring and
             | plugs you can use a 240V electric kettle in the USA just
             | fine. You may need to import a European kettle and rewire
             | it to a standard American 240V socket (or use one of those
             | travel adaptors but that may be dangerous). These sockets
             | are already used for high power devices like car chargers,
             | AC, and other heavy electrical equipment. Your kitchen may
             | even have one intended for induction cooking that you can
             | use.
             | 
             | Don't be foolish like some and have 240V wired to a
             | standard plug, though! NEMA 6-15 and 6-20 exist just so you
             | don't mistake your beefed up socket for a normal American
             | socket and fry your devices/zap yourself or others.
        
         | [deleted]
        
         | gumby wrote:
         | > problems like the grid frequency increasing and making
         | digital clocks run ahead
         | 
         | Ahem: the ones driven by the grid frequency are _analogue_
         | clocks.
         | 
         | This function was so important that if load changes caused the
         | frequency to fluctuate the power companies will compensate as
         | soon as they can to make sure the clocks can catch up. I said
         | "was" because I have no idea (and does anyone?) how many such
         | clocks are still in service. But it's a legacy function and,
         | like POTS, such features are still maintained. Because you
         | never know who'll need it.
        
           | userbinator wrote:
           | Digital clocks too. Plenty of clocks are still being
           | manufactured that rely on the grid frequency, although as
           | quartz crystals have become cheaper, some companies have
           | started using those instead of mains-referenced clocks. Yet
           | the old 70s PMOS mains-referenced clock ICs --- one of the
           | first mass-produced LSI ICs for consumer electronics --- are
           | apparently still in production and widespread use.
           | 
           | https://hackaday.com/2018/03/29/ask-hackaday-is-your-
           | clock-t...
           | 
           | It's been my experience that, in the long term, mains-
           | referenced clocks are extremely accurate, while local quartz
           | ones seem to drift significantly. Clock also tend to last
           | long enough that these are relatively common around here:
           | https://en.wikipedia.org/wiki/Telechron
        
             | naikrovek wrote:
             | yes. the US grid operators also seem do go through a lot of
             | effort to make sure there are exactly 5,184,000 cycles per
             | 24-hour period, specifically because it helps those clocks
             | keep time.
             | 
             | I don't have any clocks that do this, so I bought one of
             | these, which keeps accurate time without intervention from
             | me or the power company:
             | https://mitxela.com/projects/precision_clock_mk_iii
        
           | jeroenhd wrote:
           | Not just analogue clocks! In Europe we had our digital clocks
           | run late for quite a while after a power crisis resulting
           | from some political energy dispute in Serbia/Kosovo dropped
           | the frequency for a while. This caused all manner of clocks
           | to run late by five minutes or more. They even intentionally
           | cranked up the frequency for a while to bring those clocks
           | back in sync.
           | 
           | Alarm clocks, microwave clocks, all manner of time indicators
           | without sync mechanism built in were affected because relying
           | on Europe's near perfect 50 Hz grid frequency is pretty damn
           | cheap.
        
         | b800h wrote:
         | Can confirm to some extent - I started out in data analytics
         | for call centres, and important episodes of Eastenders et al
         | would completely bork the demand predictions by causing exactly
         | the pattern of depressed traffic followed by a massive surge
         | described in the blog post. Some of this was less about tea and
         | more about just having four television channels.
        
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