[improve] [broker] Check max producers/consumers limitation first before other ops to save resources

[poorbarcode]

Motivation

Background

• Pulsar checks compatible of schemas when adding producers/consumers
• After checking schemas, it checks the max producers/consumers count.

Issue

• If the clients have already reached max limitation of producers/consumers count, the client will try to register producers/consumers continuously.
• It checks schemas, then checks the max producers/consumers count. This will waste many CPU resources to check the compatibility of schemas.

Modifications

• Check max producers/consumers limitation first before other ops to save resources

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository: x

[crossoverJie]

Good catch, LGTM.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 92.85714% with 1 line in your changes missing coverage. Please review.

Project coverage is 73.45%. Comparing base (bbc6224) to head (a20ff14).
Report is 603 commits behind head on master.

Files with missing lines	Patch %	Lines
...rg/apache/pulsar/broker/service/AbstractTopic.java	80.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #23074      +/-   ##
============================================
- Coverage     73.57%   73.45%   -0.13%     
- Complexity    32624    33212     +588     
============================================
  Files          1877     1917      +40     
  Lines        139502   144077    +4575     
  Branches      15299    15741     +442     
============================================
+ Hits         102638   105828    +3190     
- Misses        28908    30133    +1225     
- Partials       7956     8116     +160     

Flag	Coverage Δ
inttests	27.55% <28.57%> (+2.97%)	⬆️
systests	24.76% <21.42%> (+0.43%)	⬆️
unittests	72.50% <92.85%> (-0.35%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...va/org/apache/pulsar/broker/service/ServerCnx.java	72.28% <100.00%> (+0.13%)	⬆️
...rg/apache/pulsar/broker/service/AbstractTopic.java	88.30% <80.00%> (+0.31%)	⬆️

... and 509 files with indirect coverage changes