Hacker News new | ask | show | jobs
by NikolaNovak 1077 days ago
We are running a busy self service ERP for growing 400k employees, on a single database instance for 7 years now. Currently at 256gb ram, 8tb database, 32 P9 cores. I got 99 problems but the single database server ain't one of them!
3 comments
giovannibonetti 1077 days ago
Parent was probably talking about the application server, which is the typical example of K8s usage, whereas most databases don't fit well there and are usually separate from the K8s cluster.
link
benglish11 1077 days ago
Yeah. They must be. I’ve had several k8s enthusiast dissuade from putting a db in k8s for performance reasons. This may change overtime but I believe there is a performance bottleneck in disk I/o (or at least that’s how it was explained to me)
link
mschuster91 1077 days ago
That really depends on your k8s environment. If you're running on bare metal and use host bind mounts for storage, you won't have a problem. But as soon as you introduce shared storage it gets messy...
link
tjoff 1077 days ago
Doesn't that defeat the promise of k8 in the first place?

Because then it won't scale.

And the moment you do you run into other bottlenecks.

link
mschuster91 1077 days ago
Meh, not having to worry about configuring load balancers and letsencrypt alone is worth the effort to get k8s running.
link
Mister_Snuggles 1077 days ago
We've just migrated our ERP from a regular deployment on VMs into Kubernetes. We have a very bursty self-service component, so being able to scale up easily for the week we need it is quite nice. We've taken advantage of this ability multiple times and seen great success each time.

We're not running the DB in Kubernetes though.

link
mysterydip 1077 days ago
Just curious, what backup/replication/disaster recovery solution(s) are you running with that?
link
NikolaNovak 1077 days ago
Used to run Tivoli Storage Manager, now Commvault. Backup can be used for certain type of issues that are isolated to the database.

For DR, Entire stack is being continually synced with a set of hot server in separate datacentre. We run a fully DR exercise yearly and it works well. It's a fairly proprietary AIX / DB2 method though so not sure you'd find value unless you're using the exact same technology stack :-/

link