statistics: make aot more stable

[lhy1024]

Signed-off-by: lhy1024 admin@liudos.us

What problem does this PR solve?

Issue Number: Ref #4949

What is changed and how does it work?

If DefaultAotSize is 2, a random fluctuation will affect two interval.

Check List

Tests

• Unit test

Release note

None.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• HunDunDM
• nolouch

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

The full list of commands accepted by this bot can be found here.

Reviewer can indicate their review by submitting an approval review.
Reviewer can cancel approval by submitting a request changes review.

[codecov]

Codecov Report

Merging #4951 (04e9c42) into master (d6557df) will increase coverage by 0.06%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #4951      +/-   ##
==========================================
+ Coverage   75.18%   75.25%   +0.06%     
==========================================
  Files         297      297              
  Lines       29492    29497       +5     
==========================================
+ Hits        22173    22197      +24     
+ Misses       5369     5354      -15     
+ Partials     1950     1946       -4     

Flag	Coverage Δ
unittests	75.25% <100.00%> (+0.06%)	⬆️

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

Impacted Files	Coverage Δ
server/statistics/util.go	100.00% <ø> (ø)
server/cluster/cluster.go	83.04% <100.00%> (+0.31%)	⬆️
server/core/basic_cluster.go	91.14% <100.00%> (+0.14%)	⬆️
server/storage/leveldb_backend.go	76.00% <0.00%> (-8.00%)	⬇️
client/base_client.go	79.89% <0.00%> (-2.07%)	⬇️
server/member/member.go	64.21% <0.00%> (-1.58%)	⬇️
server/region_syncer/client.go	84.21% <0.00%> (-1.51%)	⬇️
server/election/lease.go	84.05% <0.00%> (-1.45%)	⬇️
server/schedule/operator_controller.go	84.47% <0.00%> (-1.21%)	⬇️
server/region_syncer/server.go	79.89% <0.00%> (-1.09%)	⬇️
... and 16 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update d127054...04e9c42. Read the comment docs.

[nolouch]

/merge

[ti-chi-bot]

@nolouch: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 66ec8eb