Fix time.Tick leak

[dittos]

https://golang.org/pkg/time/#Tick

While Tick is useful for clients that have no need to shut down the Ticker, be aware that without a way to shut it down the underlying Ticker cannot be recovered by the garbage collector; it "leaks".

It seems to fix high CPU usage issue. (#73)

[yasker]

Thanks for the PR @dittos

I am not sure this can cause the CPU utilization issue though since this code is only called once and will be terminated with the process.

[dittos]

this code is only called once and will be terminated with the process.

Isn't time.Tick called every 30 secs in the loop?

I ran the patched version and it fixed the CPU usage increasing.

left (green): patched version / right (red): v0.0.13

Note that there was a simillar fix in the other project: cert-manager/cert-manager#2467

[yasker]

@dittos You're right. I misread the code.

Thanks for troubleshooting this! I will merge this and do a new release.