Revert "planner: merge fast plan cache and normal plan cache"

[qw4990]

What problem does this PR solve?

Issue Number: ref #50618

Problem Summary: planner: merge fast plan cache and normal plan cache

What changed and how does it work?

revert #53033, which causes some performance regression on BenchmarkPreparedPointGet: 6305 ns/op --> 9011 ns/op

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-05-07 11:29:25.403574658 +0000 UTC m=+961519.160710229: ☑️ agreed by AilinKid.
• 2024-05-07 11:33:05.517724269 +0000 UTC m=+961739.274859858: ☑️ agreed by hawkingrei.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: AilinKid, hawkingrei, winoros

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• OWNERS [AilinKid,hawkingrei,winoros]
• pkg/planner/OWNERS [AilinKid,hawkingrei,winoros]

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[codecov]

Codecov Report

Attention: Patch coverage is 87.23404% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 74.0735%. Comparing base (81a7cf5) to head (b0c4ac1).
Report is 1 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #53084        +/-   ##
================================================
+ Coverage   72.0185%   74.0735%   +2.0550%     
================================================
  Files          1508       1508                
  Lines        434859     435956      +1097     
================================================
+ Hits         313179     322928      +9749     
+ Misses       102094      92923      -9171     
- Partials      19586      20105       +519     

Flag	Coverage Δ
integration	48.8770% <76.5957%> (?)
unit	71.2294% <80.8510%> (+0.0058%)	⬆️

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

Components	Coverage Δ
dumpling	53.9957% <ø> (ø)
parser	∅ <ø> (∅)
br	46.6494% <ø> (+8.1629%)	⬆️

[qw4990]

/retest