br: Fix backupmeta division bug

[MoCuishle28]

Signed-off-by: zhanggaoming gaoming.zhang@pingcap.com

What problem does this PR solve?

Issue Number: close #37244

Problem Summary:
backupmeta is not divided as expected.

What is changed and how it works?

Check List

Tests

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

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

Manual Test

For testing, I modified MetaFileSize to 20 units.KiB. (i.e., Flush is executed when backupmeta is larger than 20 KiB.)
But in the committed code, MetaFileSize is still 128 * units.MiB.

tidb/br/pkg/metautil/metafile.go

Line 44 in d1f75f0

MetaFileSize = 128 * units.MiB

Run br backup full -u '{IP}:{Port}' -s '{path}' --use-backupmeta-v2=true

Detail BR log in /tmp/br.log.2022-08-22T15.44.54+0800 
Full Backup <--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------> 100.00%
Checksum <-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------> 100.00%
[2022/08/22 15:45:42.462 +08:00] [INFO] [collector.go:69] ["Full Backup success summary"] [total-ranges=264] [ranges-succeed=264] [ranges-failed=0] [backup-checksum=11.125195947s] [backup-fast-checksum=53.509755ms] [backup-total-ranges=89] [backup-total-regions=244] [total-take=48.402973686s] [BackupTS=435461631597346817] [total-kv=108954045] [total-kv-size=12.51GB] [average-speed=258.5MB/s] [backup-data-size(after-compressed)=4.843GB] [Size=4843046770]

Run du -sh * in backup dir

4.0K    backup.lock
4.0K    backupmeta
24K     backupmeta.datafile.000000001
24K     backupmeta.datafile.000000002
24K     backupmeta.datafile.000000003
4.0K    backupmeta.datafile.000000004
24K     backupmeta.schema.000000005
24K     backupmeta.schema.000000006
24K     backupmeta.schema.000000007
24K     backupmeta.schema.000000008
24K     backupmeta.schema.000000009
24K     backupmeta.schema.000000010
24K     backupmeta.schema.000000011
24K     backupmeta.schema.000000012
28K     backupmeta.schema.000000013
8.0K    backupmeta.schema.000000014

drop database

Run br restore full -u '{IP}:{Port}' -s '{path}'

Detail BR log in /tmp/br.log.2022-08-22T15.59.49+0800 
Full Restore <-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------> 100.00%
[2022/08/22 16:00:39.523 +08:00] [INFO] [collector.go:69] ["Full Restore success summary"] [total-ranges=256] [ranges-succeed=256] [ranges-failed=0] [split-region=227.871055ms] [restore-ranges=176] [total-take=50.097892323s] [total-kv=108910298] [total-kv-size=12.51GB] [average-speed=249.6MB/s] [restore-data-size(after-compressed)=4.842GB] [Size=4842191785] [BackupTS=435461866045833217]

Release note

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

None

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• 3pointer
• joccau

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[MoCuishle28]

/run-integration-br-test

[MoCuishle28]

/component br

[sre-bot]

Code Coverage Details: https://codecov.io/github/pingcap/tidb/commit/0563391ca7fd30337a3643d13b0a767e357d2f19

[MoCuishle28]

/run-build

[MoCuishle28]

/run-integration-br-test

[MoCuishle28]

/run-integration-br-test

[ti-chi-bot]

@WangLe1321: Thanks for your review. The bot only counts approvals from reviewers and higher roles in list, but you're still welcome to leave your comments.

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[joccau]

LGTM

[3pointer]

/merge

[ti-chi-bot]

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

Commit hash: 0563391

[sre-bot]

TiDB MergeCI notify

🔴 Bad News! [2] CI still failing after this pr merged.
These failed integration tests don't seem to be introduced by the current PR.

CI Name	Result	Duration	Compare with Parent commit
idc-jenkins-ci-tidb/common-test	🔴 failed 1, success 10, total 11	12 min	Existing failure
idc-jenkins-ci-tidb/integration-common-test	🔴 failed 1, success 16, total 17	12 min	Existing failure
idc-jenkins-ci/integration-cdc-test	🟢 all 36 tests passed	26 min	Existing passed
idc-jenkins-ci-tidb/tics-test	🟢 all 1 tests passed	7 min 35 sec	Existing passed
idc-jenkins-ci-tidb/integration-ddl-test	🟢 all 6 tests passed	5 min 2 sec	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-2	🟢 all 28 tests passed	4 min 41 sec	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-1	🟢 all 26 tests passed	4 min 3 sec	Existing passed
idc-jenkins-ci-tidb/mybatis-test	🟢 all 1 tests passed	3 min 31 sec	Existing passed
idc-jenkins-ci-tidb/integration-compatibility-test	🟢 all 1 tests passed	2 min 46 sec	Existing passed
idc-jenkins-ci-tidb/plugin-test	🟢 build success, plugin test success	4min	Existing passed