[JENKINS-27650] TCB plugin performance (extra caching)

[oleg-nenashev]

The approach is not ready (see the idea in #27 ).

• It provides some performance advantages on overloads in "categories" mode, but I'm still able to overload Jenkins.
• Job configuration updates should be handled. Currently cache may become inconsistent if somebody adds/removes configurations to jobs during their execution

Merge with #27 is also required

[oleg-nenashev]

It was a bad idea from another commit. I'll rework it

[jglick]

type can be omitted BTW

[jglick]

Merging with #27 will be hard. Probably you could just merge the first three commits, but the fourth (Snapshot) would need to be recreated.

This seems risky: code mistakes or oversights could easily lead to a stale cache.

[oleg-nenashev]

This seems risky: code mistakes or oversights could easily lead to a stale cache.

Yes, I'm also aware about it. I consider flushing the cache on updates and other conditions. There's still a risk of false-negatives deadlock if something is implemented incorrectly. Probably, a periodic cache cleanup (e.g. every 1 minute) could prevent it

[jenkinsadmin]

Thank you for a pull request! Please check this document for how the Jenkins project handles pull requests

[basil]

@oleg-nenashev The last update to this PR was 4 years ago. Can this PR be closed to clean up the open pull requests list?