v5.0.6 upgrade to v6.4.0, tiflash keeping restart for "[FATAL] [config.rs:400] ["invalid configuration: max_background_jobs should be greater than 0 and less than or equal to 0"]"

[seiya-annie]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

1. v5.0.6 upgrade to v6.4.0

2. What did you expect to see? (Required)

upgrade successfully

3. What did you see instead (Required)

upgrade fail

4. What is your TiFlash version? (Required)

[2022/11/08 00:41:27.675 +08:00] [INFO] [] ["Welcome to TiFlash"] [thread_id=1]
[2022/11/08 00:41:27.675 +08:00] [INFO] [] ["Starting daemon with revision 54381"] [thread_id=1]
[2022/11/08 00:41:27.675 +08:00] [INFO] [] ["TiFlash build info: TiFlash\nRelease Version: v6.4.0\nEdition: Community\nGit Commit Hash: 301561b\nGit Branch: heads/refs/tags/v6.4.0\nUTC Build Time: 2022-11-07 10:12:06\nEnable Features: jemalloc sm4(GmSSL) avx avx512 unwind thinlto\nProfile: RELWITHDEBINFO\n"] [thread_id=1]

[seiya-annie]

log :
tiup.deploy.tiflash-9000.log.tar.gz

[CalvinNeo]

The error is

invalid configuration: max_background_jobs should be greater than 0 and less than or equal to 0

The second 0 is strange.
We observe cpu quota is

[2022/11/08 00:39:38.494 +08:00] [INFO] [config.rs:354] ["quota: cpu 0.6 mem in bytes 5905580032"]

Which makes the following code equal to 0.

let limit = SysQuota::cpu_cores_quota() as i32 * 10;

[CalvinNeo]

We need cpu quota to be greater than 1 for now.
See tikv/tikv#13752.