P1-[4.0 bug hunting]-[Dashboard]-wrong memory usage info for TiFlash

[sre-bot]

Bug Hunter issue tidb-challenge-program/bug-hunting-issue#91

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1. What did you do?

• deploy a cluster on Aliyun with tiup
• visit PD's dashboard -- cluster info -- hosts

2. What did you expect to see?

TiFlash's memory usage is correct

3. What did you see instead?

TiFlash's memory usage is incorrect

I have another cluster which deployed on Tencent Cloud, the TiFlash node on that also shows a memory usage at 96.2%, but actually the node only has a memory usage at 65%

4. What version of TiDB are you using? (tidb-server -V or run select tidb_version(); on TiDB)

root@node3:~# /tidb-deploy/tidb-4000/bin/tidb-server -V
Release Version: v4.0.0-rc.2
Edition: Community
Git Commit Hash: dfbb1ff8b0a8d55893bcea652748c40b9a9b91ad
Git Branch: heads/refs/tags/v4.0.0-rc.2
UTC Build Time: 2020-05-15 11:54:25
GoVersion: go1.13
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false

[breezewish]

According to tidb-challenge-program/bug-hunting-issue#91 this issue is fixed for master branch.

[breezewish]

I think this issue should be opened in TiDB Dashboard repo instead.

[fzhedu]

redirect to pingcap/tidb-dashboard#744, so close it here.