hot metrics still stop last value when a store meets pending

[lhy1024]

Bug Report

What did you do?

run benchmark and meet a pending store

What did you expect to see?

metrics drop to zero

What did you see instead?

store read bytes and store read query stop last value

What version of PD are you using (pd-server -V)?

master

[mayjiang0203]

/severity moderate
/remove-severity major
Since it only occur when io blocked but tikv instance still up.

[mayjiang0203]

/label affects-4.0
/label affects-5.0
/label affects-5.1
/label affects-5.2
/label affects-5.3
/label affects-5.4
/label affects-6.0
/label affects-6.1

[ti-chi-bot]

@mayjiang0203: The label(s) affects-6.1 cannot be applied. These labels are supported: Hacktoberfest, challenge-program, ci-unstable, compatibility-breaker, high-performance, hptc, needs-cherry-pick-release-1.0, needs-cherry-pick-release-2.0, needs-cherry-pick-release-2.1, needs-cherry-pick-release-3.0, needs-cherry-pick-release-3.1, needs-cherry-pick-release-4.0, needs-cherry-pick-release-5.0, needs-cherry-pick-release-5.1, needs-cherry-pick-release-5.2, needs-cherry-pick-release-5.3, needs-cherry-pick-release-5.4, needs-cherry-pick-release-6.0, needs-cherry-pick-release-6.1, release-note, require-LGT1, wontfix, affects-4.0, affects-5.0, affects-5.1, affects-5.2, affects-5.3, affects-5.4, affects-6.0, may-affects-4.0, may-affects-5.0, may-affects-5.1, may-affects-5.2, may-affects-5.3, may-affects-5.4, may-affects-6.0.

In response to this:

/label affects-4.0
/label affects-5.0
/label affects-5.1
/label affects-5.2
/label affects-5.3
/label affects-5.4
/label affects-6.0
/label affects-6.1

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.

[mayjiang0203]

/label affects-6.1