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Obviously we need more breasts "for training."

Note that they were running psql on ec2 instances, which implies bare metal with SSDs.

Yes you can get actual hosts in AWS if you pay for them.

The article also implies that they were never able to get psql to replicate effectively.

Whomever their DBA was was couldn't do it, so they were like "fuck it, let's move to Aurora." Their database brought no actual value, so it make sense for them.


They likely were running data on EBS volumes instead of bare metal SSDs, due to ease of recovery (a failed instance does not lose data on the attached EBS volumes). You can only run your DBs on bare metal SSDs if you are prepared to lose a node’s data completely.

In fact, many instance types no longer have any ephemeral storage attached and it’s a default practice to use EBS for root and data volumes.

There are some instance types that have extremely fast EBS performance (EBS io2 Block Express), which has hardware acceleration and an optimized network protocol for EBS network I/O and offers sub-millisecond latency. However, these are expensive and get even more so if you go up in IOPS.


I'd argue you need the infrastructure to recover from loss of a host regardless if you have backups setup properly.

Using EBS seems like a total anti-pattern for DB workloads.


> Note that they were running psql on ec2 instances, which implies bare metal with SSDs.

No, this doesn't imply SSDs.

EC2 instances do not have access to SSDs but to EBS volumes which is a much slower distributed network block storage medium.

Not sure about their PostgreSQL replication issues but lots of companies manage to make it work without a hitch.


You can have EC2s with ssds. But generally the workflow for running your own DB is smart caching in memory on top of whatever storage you got.

The problem with the metal instances you are referring to is that the SSD is lost if you stop and start the server.

I wonder if he still has a job? Running all your postgres on ec2 is like 1000X harder than looking at the dashboard for an Aurora cluster.

The amount of ingredient in the pill is huge relative to the shot, and you need to take it daily...which shows how hard it is to get drugs into the body.

Real question: given the dosage, how would you go about getting the pill and liquefying it? That would provide a huge, cheap supply of semaglutide.


The reason you didn't just drop stuff in /usr/local? Space.

One of our devs was also a gimp contributor, and he dropped gimp into /usr/local and filled up the filesystem. And back then package managers didn't exist, so you had to read the makefile and hope you didn't remove anything that was shared

/opt/gimp or /usr/local/gimp.

Local because in some places they mounted an nfs share, and local was local to you.


Knee replacement surgeons should be worried. Both my father and FIL had their knees replaced.

I'd like to think orthopedists would rather be overjoyed at this. My wife had her knee and hip done by a cracking orthopedist, and his primary concern was her quality of life. He even went to the state physicians' board to argue that her hip surgery should be considered necessary rather than elective for purposes of COVID restrictions, so that we could get it done months before it was originally scheduled.

afaik surgeons are able to perform quite a few types of surgeries, obviously the ones working on brains more advanced than ones working on knees it's probably only a few years to transition to a different type of category.

Again, the cost is in storage, not generation. But it looks like LiFePO4 batteries are the way forward these days.


Nobody seems to have asked the US Navy about the crash. The Indian Ocean is a well-known hangout for boomers, and the USN listening posts should have heard the crash.


I think the theory is, even if they heard something, they would've shrugged (1) and said "I dunno", because they don't want to reveal to e.g. the Chinese about their listening capabilities.

The sentence is also true if you replace "they" with "the Chinese Navy" and "Chinese" with "Americans".

(1) https://media.tenor.com/zDbPxZJwlFQAAAAM/shrug.gif


It's actually not bullshit. Saving time is worth it. People use that metric when sitting in traffic...why not use it for computer response time?

How many decades have been wasted in Windows waiting for updates?


Saving time is not bullshit, equating it to "saving lives" is.


Awesome!

Good engineering: when you're not too proud to do the obvious, but sort of cheesy-sounding solution.


I have two solar panels that can generate around 960w/hr. Both panels cost around $400 ($200x2). Cheap.

Storing that energy is quite expensive. an Anker Solix 3800, which is around 3.8kwh, costs $2400 USD. To store 10kwh would cost $7200 USD (which gets us more than 10kwh).

If that cost asymmetry can come down then it becomes feasible to use solar power to provide cheap/local electricity in poor countries at a house scale.


There are way cheaper options than the Anker Solix 3800. Here are some options, in no particular order:

- $3,300: 10 kWh with 2x EG4 WallMount Indoor 100Ah.

- $3,110: 14 kWh with 1x WallMount Indoor 280Ah.

- $2,690: 10 kWh with 1x Deye RW F10.2 B

- Will Prowse's YouTube channel has reviewed several battery builds that are >10 kWh and near $2,000, but they're DIY assembly.


Batteryhookup has batteries for $40/kWh :) just put together a off grid setup for a friend and 8kwh cost $400 in parts!


I'll check that out. The goal is to get to something that runs all night (or almost all night) with around 1kwh output using as little space as possible. I've just started poking around, but this'll help.

In the third world there's plenty of sunlight, but you don't need the power during the day necessarily. That price'll get to $400 for storage, $400 for panels, which is ballpark.


And still much more than the cost of the solar panels, which was GP's point.


GP only has two panels that generate 960 W (I’m going to generously assume NMOT and not STC). That’s hardly anything, and certainly not what I would use to try and charge 10 kWh of battery like they’re suggesting.

But sure, I agree it would help if battery prices came down.


During the day when nobody's home the panels are charging the battery.

Obviously more panels are better.

The goal is to be able to run a small window AC unit and various small appliances at night. That's a tremendous quality-of-life upgrade for a huge number of people. $1000 USD would make it somewhat affordable, in the window for a viable small business/NGO opportunity. There's obviously a whole lot more (installation, labor, maintenance, etc), but material cost needs to be low for it to work.


The YouTuber Will Prowse has an excellent site where he tracks his most recommended batteries (and other equipment like inverters) at any time. The prices are always changing, and there are new products all the time so check on the his list any time you are looking to buy:

https://www.mobile-solarpower.com

Like the other commenter said, batteries are a lot cheaper if you are willing to shop around. His top recommended budget battery today is a 4x your Anker Solix's capacity, and around 1/4th the price. You can find many 5kWh server rack batteries for under $1000 now.


Here's a quote I got for a solar install in the Philippines this week:

51.2v 314ah cells (15kwh battery) 16x 580-590w solar panel

Installed for 310k PHP = $5,275

I've also specced out 15-16kwh batteries using the Yxiang design for around the price of your Solix. The problem in the US is regulatory and a particularly predatory tradesman market at the moment.


Is that "regulatory" the problem or is it the solution? We'll know more 20 years from now, looking back at fire incident statistics.

(yes, I'm leaving it open if regulation makes a difference or not - for all we know it could even make a negative difference, helping companies that are better at regulation than at safety. But if I had to bet, I know where my money would be)


Western storage options are very expensive.

We are starting to see Chinese options pop up but not sure if I would install them yet.

https://www.docanpower.com/eu-stock/zz-48kwh-50kwh-51-2v-942...


Wait that Anker Solix 3800 costs more than my 84kwh battery containing _car_ (3.8 kwh x 22 batteries)? Something not right.


Are you saying you bought an electric car with functional 84kwh pack for less than 3 grand? If so I think the outlier is you. That is a better deal than I have seen.


Did I read incorrectly?

> which is around 3.8kwh, costs $2400 USD. To store 10kwh would cost $7200 USD (which gets us more than 10kwh).

84kwh / 3.8 kwh is about 22. 22 * 2400 is ~53k.


The batteries in MWh range cost around 160 EUR/kWh all in. Including grid connection and BOP.


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