On Mon, Nov 28, 2022 at 10:49:28AM +0100, Aurelien Bompard wrote:
> - You'll need to share the same redis password across
several projects.
Redis does have users and permissions, at least from a quick look at
their docs:
https://docs.redis.com/latest/rc/security/database-security/passwords-use...
> - Since you'll use an emptyDir (in-memory storage), every restart will flush the
cache for all connected applications.
I was thinking of running Redis in a VM, not in OpenShift. Sorry if
that wasn't clear in my initial message.
> - Applications owners lose control over the redis instance in case they want to do
some fancy stuff with it, or just general debugging.
True.
> It avoids a single point of failure for a bunch of services.
Right, but that's what our PostgreSQL host is at the moment already.
Yeah, true. I have thought about splitting that out too, but I am not
sure if I think it's a good idea to have databases in openshift and
making them vm's adds overhead of more vm's.
> Contention/resource problems. (ie, one app is hammering the
shared instance and starving other apps for resources).
True, true.
OK, that makes sense. The good thing about having a central Redis DB
was, in my mind, to have persistent storage. What happens if I store a
lot of data in the Redis Openshift pod? Won't that hit a memory limit?
I think our current usage of Redis has been pubsub and light cache,
but we haven't stored a lot of data in there yet.
Well, we can actually do persistent storage in the ocp4 cluster. ;)
There's nfs volumes, but also there's a local ceph storage (using disk
on the compute nodes). I'm not sure how slow/fast it might be, but it is
there...
kevin