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What One-person SaaS Healthchecks.io uses for hosting, hardware and software

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Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#161

Post by mdasen »

cuu508 wrote: post #32
tothrowaway wrote: post #12

Can you share more details about what the 4 HAProxy servers are doing? I run a SaaS too, but on a single beefy machine handling web and DB stuff. I'm curious what I'm missing out on not using HAProxy in front.

To answer the question of why four of them: * the traffic from the monitored systems comes with spikes. Looking at netdata graphs, currently the baseline is 600 requests/s, but there is a 2000 requests/s spike every minute, and 4000 requests/s spike every 10 minutes. * want to maintain redundancy and capacity even when a load balancer is removed from DNS rotation (due to network problems, or for upgrade) There are sp…

I understand having multiple proxies, but it seems a bit odd to have more proxy servers than web servers, no? Do they also do caching so that of the up-to 4,000 requests/second, a lot of them never reach the web servers? Presumably the Python code is more resource intensive than HAProxy.

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#162

Post by lazide »

mlyle wrote: post #143
wildmanx wrote: post #122

Earlier quoted context omitted.

As a counter argument, imagine an infinitely good insulation and 0 standby power (and a spherical cow inside, for illustration purposes). Then keeping it "running" is clearly better than letting the fridge warm up since power draw is 0 in the former case. Obviously the conditions are not as perfect, but with a very modern fridge, maybe you get sufficiently close that keeping running indeed is superior. I'm not arguin…

> imagine an infinitely good insulation Then it would never warm up, and at this limit the two cases are equivalent (powered and unpowered). > when approaching the mentioned fantasy conditions, beyond which letting it run may be better. Anywhere short of the limit, what I said holds. Anything better than infinite insulation, I don't know how to reason about.

I think you're missing the point.

Perfect insulation doesn't help if you open the door?

If you're saying 'well with perfect insulation it doesn't matter if it has power' - well yeah. It doesn't matter if it has power. So you aren't wasting any either leaving it on.

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#163

Post by sigg3 »

8fingerlouie wrote: post #159
sigg3 wrote: post #130

Earlier quoted context omitted.

As a Norwegian looking into solar for my garage, all the products available now produce power when it's cloudy, snowy, rainy etc. First Google result: https://www.energy.gov/eere/solar/articles/busted-common-sol...

I’m not saying it wouldn’t produce energy, and it would probably also contribute most of the year, but the time where I need the most energy (heating and light) is also the time where it is least likely to produce any. We have an annual power consumption of 6-8k kWh, with about half during winter (heat pump, yay). More energy is required during night time due to dropping temperatures and it being dark, so realistical…

Yes, the ROI takes years to achieve but the alternative is to keep throwing money at the power company (and some of that energy will likely be from coal nowadays).

Since I bought an electric car I've been drooling over the idea of having the car powered by the sun. I go into the office only on occasion so I don't need to charge fast either. But you need an available roof and an okay topography.

But in Scandinavia, I bet most energy goes to heating so improving insulation and adding ground thermal will probably be more efficient. The idea of a sun powered car is just so enticing, however. It's kinda sci-fi.

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#164

Post by gituliar »

sdevonoes wrote: post #155
metafunctor wrote: post #154

Earlier quoted context omitted.

They do provide private networks now, but AFAIK they didn't in 2017. Today, one could use “vSwitch” or “Cloud Network”, or both, to set up private networking. But, if you want to easily encrypt all traffic, Wireguard might still be a good idea.

Good to know. > But, if you want to easily encrypt all traffic, Wireguard might still be a good idea. But, if one is already using https I guess encrypting the traffic would be unnecessary, no?

My guess: https hits HAProxy from external world, afterwards all is just http. There is no need to encrypt internal trafic.

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#166

Post by mlyle »

lazide wrote: post #162
mlyle wrote: post #143

Earlier quoted context omitted.

> imagine an infinitely good insulation Then it would never warm up, and at this limit the two cases are equivalent (powered and unpowered). > when approaching the mentioned fantasy conditions, beyond which letting it run may be better. Anywhere short of the limit, what I said holds. Anything better than infinite insulation, I don't know how to reason about.

I think you're missing the point. Perfect insulation doesn't help if you open the door? If you're saying 'well with perfect insulation it doesn't matter if it has power' - well yeah. It doesn't matter if it has power. So you aren't wasting any either leaving it on.

Heat losses are proportional to the temperature difference integrated over time, and the refrigerator is more efficient in taking heat from the inside when it is close to the temperature of the room. This means that you are better off letting it warm up, because this results in both types of losses decreasing.

This continues all the way up to perfect insulation, though ultimately it's breakeven with perfect insulation.

> Perfect insulation doesn't help if you open the door?

This doesn't change the picture, but worse, it's just completely unrelated to the scenario. Who's opening the door when everyone has left for weeks?

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#167

Post by nijave »

threeseed wrote: post #33
skc wrote: post #30

Earlier quoted context omitted.

> I wish every project was as basic as a web server and database but it's pretty rare these days. I feel like the overwhelming majority of web based software projects can be catered for with exactly this setup. If it's rare it's because everybody's drunk the Kool-aid

Maybe in the past, sure. But these days people rely far more on their web apps. Having a 1-2 day outage because your architecture is not highly-available across data centres like this one just doesn't cut it. And multi-day outages are very much real because of the thundering herd effect as companies rapidly try to move between data centres exhausting capacity. And much of the complexity in modern day architectures co…

The post mentions he picked multiple Hetzner DCs to put his servers in

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#168

Post by nijave »

capableweb wrote: post #18
threeseed wrote: post #13

Earlier quoted context omitted.

> This is just slightly more complex than a static site That's because their product is only slightly more complex than a static site. I wish every project was as basic as a web server and database but it's pretty rare these days.

> I wish every project was as basic as a web server and database but it's pretty rare these days. Is it? What functionality are you thinking about that absolutely require more than that? I find that most ideas even today can be solved with a web server + DB, while developers today like to over-engineer things and think about scaling a service for a million users while they haven't even figured out the value propositi…

The last couple places I worked also had a queueing system for async execution/background tasks.

A lot of apps use an "AI" or "machine learning" component which usually just means a second heterogeneous internal service.

For a little bit larger companies it's pretty common to have a data analytics or data warehouse component.

In addition, a web server + database usually require some monitoring system. After you have more than a handful of servers, probably also log aggregation.

If you're just a single or handful of people working on something, you probably don't need any of that.

Once you get a little bigger (or downtime becomes expensive) those things get tacked on quickly.

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#169

Post by lazide »

mlyle wrote: post #166
lazide wrote: post #162

Earlier quoted context omitted.

I think you're missing the point. Perfect insulation doesn't help if you open the door? If you're saying 'well with perfect insulation it doesn't matter if it has power' - well yeah. It doesn't matter if it has power. So you aren't wasting any either leaving it on.

Heat losses are proportional to the temperature difference integrated over time, and the refrigerator is more efficient in taking heat from the inside when it is close to the temperature of the room. This means that you are better off letting it warm up, because this results in both types of losses decreasing. This continues all the way up to perfect insulation, though ultimately it's breakeven with perfect insulatio…

Uh no. The heat pump may be more efficient during the period it has the largest temperature differential, but that is ensuring it has the largest possible heat differential up front. If you don’t do that (aka keep it on), there is far less total heat to move, unless you’d have it sit so long that you’d get the same total heat transfer. Which if the insulation is good, may take many weeks.

Which seems unlikely in this case.

My chest freezer for instance turns on for less than 30 minutes a day even with people getting in and out. When I defrost it, it takes a day+ to cool down again.

The reason someone would leave the door open is to ensure no one accidentally left a jug of milk in there when they turned it off. Which would pretty much neutralize any possible gains in sheer grossness if nothing else.

Re: What One-person SaaS Healthchecks.io uses for hosting, hardware and software

#170

Post by mlyle »

lazide wrote: post #169
mlyle wrote: post #166

Earlier quoted context omitted.

Heat losses are proportional to the temperature difference integrated over time, and the refrigerator is more efficient in taking heat from the inside when it is close to the temperature of the room. This means that you are better off letting it warm up, because this results in both types of losses decreasing. This continues all the way up to perfect insulation, though ultimately it's breakeven with perfect insulatio…

Uh no. The heat pump may be more efficient during the period it has the largest temperature differential, but that is ensuring it has the largest possible heat differential up front. If you don’t do that (aka keep it on), there is far less total heat to move, unless you’d have it sit so long that you’d get the same total heat transfer. Which if the insulation is good, may take many weeks. Which seems unlikely in this…

> you don’t do that (aka keep it on), there is far less total heat to move, unless you’d have it sit so long that you’d get the same total heat transfer.

I think you're a little confused. I'm a little lost at even how to minimally explain it to you. The rate at which heat leaks into the refrigerator declines as the refrigerator heats up, so this metric too improves with time.

> Which if the insulation is good, may take many weeks.

Implausible. "Many weeks"?

The best 20 cu ft refrigerators use about 375 kilowatt-hours per year according to energystar.gov. At a coefficient of performance of 10, that's an average of 400W flowing into the fridge and needing to be removed by the refrigerator.

At 20K of temperature difference, that's about 20W/degK. The contents will warm very quickly, absent phase change.

Having ice in there will slow things down until the ice melts; then it will warm very quickly. The typical numbers cited say you have 2-3 days with a full freezer without power before things have mostly thawed and become unsafe-- this is well over half of the way to room temperature in terms of energy budget (and in the best case of a full freezer where there's the most thermal mass inside).

(Specific heat capacity of water ~4200 J/(kg*k); heat of fusion of water ~334000 J/(kg*k)).

None of this changes the energy balance of the problem, though.

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