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Running Postgres in Kubernetes [pdf]

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Re: Running Postgres in Kubernetes [pdf]

#2

Post by aprdm »

That looks very interesting and super complex.

I wonder how many companies really need this complexity, I bet 99.99% of the companies could get away with vertical scaling the writes and horizontal scaling the read only replica which would reduce the number of moving parts a lot.

I have yet to play much with kubernetes but when I see those diagrams it just baffles me how people are OK with running so much complexity in their technical stack.

Re: Running Postgres in Kubernetes [pdf]

#4

Post by mamon »

aprdm wrote: post #2

That looks very interesting and super complex. I wonder how many companies really need this complexity, I bet 99.99% of the companies could get away with vertical scaling the writes and horizontal scaling the read only replica which would reduce the number of moving parts a lot. I have yet to play much with kubernetes but when I see those diagrams it just baffles me how people are OK with running so much complexity i…

It actually is not that complex. I'm using Crunchy Postgres Operator at my current employer. You get an Ansible playbook to install an Operator inside Kubernetes, and after that you get a commandline administration tool that let's you create a cluster with a simple

pgo create cluster

command.

Most administrative tasks like creating or restoring backups (which can be automatically pushed to S3) are just one or two pgo commands.

The linked pdf looks complex, because it:

a. compares 3 different operators

b. goes into implementation details that most users are shielded from.

And I'm actually not sure which one of the three operators is the author recommending :)

Re: Running Postgres in Kubernetes [pdf]

#5

Post by ghshephard »

kgraves wrote: post #3

What's the use-case for running databases in k8s, is this a widely accepted best practice?

I guess I look at it the opposite way - which is why wouldn't you run everything in k8s once you have the basic investment in it. Let's you spin up new environments, vertical scaling becomes trivial, disaster recovery/business continuity is automatic along with everything else in your k8s environment.

Re: Running Postgres in Kubernetes [pdf]

#6

Post by wiml »

aprdm wrote: post #2

That looks very interesting and super complex. I wonder how many companies really need this complexity, I bet 99.99% of the companies could get away with vertical scaling the writes and horizontal scaling the read only replica which would reduce the number of moving parts a lot. I have yet to play much with kubernetes but when I see those diagrams it just baffles me how people are OK with running so much complexity i…

I've come to the conclusion that, much like how purchasing decisions seem irrational until you realize that different kinds of purchases come out of different budgets, there are different "complexity budgets" or "ongoing operational maintenance burden" budgets in an organization, and some are tighter than others.

Re: Running Postgres in Kubernetes [pdf]

#7

Post by etxm »

kgraves wrote: post #3

What's the use-case for running databases in k8s, is this a widely accepted best practice?

Losing your data.

JK, sort of.

My first go to is something like RDS, but I’ve run Postgres in k8s for pretty much one use case: everything else is already in k8s _and_ I need a PG extension/functionality not present in RDS.

Re: Running Postgres in Kubernetes [pdf]

#8

Post by adamcharnock »

aprdm wrote: post #2

That looks very interesting and super complex. I wonder how many companies really need this complexity, I bet 99.99% of the companies could get away with vertical scaling the writes and horizontal scaling the read only replica which would reduce the number of moving parts a lot. I have yet to play much with kubernetes but when I see those diagrams it just baffles me how people are OK with running so much complexity i…

I generally work with smaller companies, but early on (Kubernetes 1.4 ish) I found that hosting mission-critical stateful services inside Kubernetes was more trouble than it was worth. I now run stand-alone Postgres instances in which each service has its own DB. I’ve found this very reliable.

That being said, I think Kubernetes now has much better support for this kind of thing. But given my method has been so stable, I just keep on going with it.

Re: Running Postgres in Kubernetes [pdf]

#9

Post by dkhenry »

kgraves wrote: post #3

What's the use-case for running databases in k8s, is this a widely accepted best practice?

I don't think its a widely accepted best practice yet, mainly because its hard to do well, and by its self its hard to take advantage of the benefits of using k8s. The company I work for has been building out the tools require to run databases well in k8s ( fully automated, fully managed, survivable, and scale-able ) and we are seeing people come around to it. Once you have all the tools in place you can have a system that scales right along side your applications on heterogeneous hardware. Isn't dependent on any single server, can be deployed and managed exactly like your applications, and can be transported everywhere. If you want to take a look check out planetscale.com
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