Add checks before adding custom config while validating

[raghu-nandan-bs]

Fixes #484

Changes proposed on the PR:

• add checks before appending customConfig to redis object's spec

[raghu-nandan-bs]

@ese @samof76 this is a trivial fix, we can evaluate using map[string]bool instead of slice to avoid nested for loops.
please share your opinions on this.

[samof76]

@ese this fixes the memory bloat issue in the operator. Can you please merge this?

[Wouter0100]

I also think this is closely related to the CPU issue I'm seeing, besides the fact that this also seems to increase network traffic.

When doing a tcpdump from a redis-operator pod, I see a lot of traffic. An increasing number of config set commands each sync is increasing.

[raghu-nandan-bs]

updated PR with fixes suggested by @samof76

@Wouter0100 that is true, it incrementally makes more and more SetRedisCustomConfig calls each iteration. it is going to be a huge stress on redis instances especially if operator is long-running.

[samof76]

@ese can you please review this?

[Wouter0100]

I have deployed the fix into one of our production and staging env, and it clearly shows an improvement.

As you might be able to guess, I deployed it at around 2AM. The CPU was constantly increasing due to the load of sending more and more network traffic.

[samof76]

@ese could you kindly review this?

[raghu-nandan-bs]

Hi @ese please do review this; this should potentially fix couple of open issues: #410 and #386

[Wouter0100]

@samof76 / @raghu-nandan-bs if you want to deploy this fix to production, I have prepared a container for it.

wouter0100/redis-operator:485

[raghu-nandan-bs]

@samof76 / @raghu-nandan-bs if you want to deploy this fix to production, I have prepared a container for it.

wouter0100/redis-operator:485

thanks @Wouter0100

[ese]

Thanks! sorry for the delay to take a look.