Fix flaky test_pdisk_slot_size_in_units.py

[rosik]

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

• Close Mute ydb/tests/functional/blobstorage/test_pdisk_slot_size_in_units.py.TestPDiskSlotSizeInUnits.test_change_pdisk_slot_size_in_units in main #29195

[github-actions]

⚪ 2025-11-21 22:32:42 UTC Pre-commit check linux-x86_64-relwithdebinfo for a2e1734 has started.
⚪ 2025-11-21 22:32:59 UTC Artifacts will be uploaded here
⚪ 2025-11-21 22:35:09 UTC ya make is running...
🟢 2025-11-21 22:38:54 UTC Tests successful.

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
37	36	0	0	0	1

🟢 2025-11-21 22:39:01 UTC Build successful.
🟢 2025-11-21 22:39:17 UTC ydbd size 2.3 GiB changed* by 0 Bytes, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 6a893e7	merge: a2e1734	diff	diff %
ydbd size	2 454 697 008 Bytes	2 454 697 008 Bytes	0 Bytes	0.000%
ydbd stripped size	523 129 656 Bytes	523 129 656 Bytes	0 Bytes	0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2025-11-21 22:33:35 UTC Pre-commit check linux-x86_64-release-asan for a2e1734 has started.
⚪ 2025-11-21 22:33:53 UTC Artifacts will be uploaded here
⚪ 2025-11-21 22:36:06 UTC ya make is running...
🟢 2025-11-21 22:41:00 UTC Tests successful.

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
35	35	0	0	0	0

🟢 2025-11-21 22:41:06 UTC Build successful.
🟢 2025-11-21 22:41:25 UTC ydbd size 3.8 GiB changed* by 0 Bytes, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 6a893e7	merge: a2e1734	diff	diff %
ydbd size	4 109 043 864 Bytes	4 109 043 864 Bytes	0 Bytes	0.000%
ydbd stripped size	1 527 256 560 Bytes	1 527 256 560 Bytes	0 Bytes	0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

🟢 2025-11-21 22:33:52 UTC The validation of the Pull Request description is successful.

[Copilot]

Pull request overview

This PR fixes a flaky test by addressing non-deterministic ordering and timing issues in the PDisk slot size test. The changes include sorting groups for consistency, removing an unreliable assertion, and adding proper wait logic for configuration updates.

• Sorts self.groups by GroupId to ensure deterministic ordering when accessed by index
• Removes an unreliable BSC PDisk check from test_change_group_size_in_units
• Adds a retryable wait for BSC updates before validating PDisk configuration changes

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[github-actions]

⚪ 2025-11-21 23:22:07 UTC Pre-commit check linux-x86_64-relwithdebinfo for fddcdb8 has started.
⚪ 2025-11-21 23:22:16 UTC Artifacts will be uploaded here
⚪ 2025-11-21 23:23:58 UTC ya make is running...
🟢 2025-11-21 23:27:18 UTC Tests successful.

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
37	37	0	0	0	0

🟢 2025-11-21 23:27:26 UTC Build successful.
🟢 2025-11-21 23:27:40 UTC ydbd size 2.3 GiB changed* by 0 Bytes, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 6a893e7	merge: fddcdb8	diff	diff %
ydbd size	2 454 697 008 Bytes	2 454 697 008 Bytes	0 Bytes	0.000%
ydbd stripped size	523 129 656 Bytes	523 129 656 Bytes	0 Bytes	0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2025-11-21 23:23:36 UTC Pre-commit check linux-x86_64-release-asan for fddcdb8 has started.
⚪ 2025-11-21 23:23:46 UTC Artifacts will be uploaded here
⚪ 2025-11-21 23:25:27 UTC ya make is running...
🟢 2025-11-21 23:29:48 UTC Tests successful.

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
35	35	0	0	0	0

🟢 2025-11-21 23:29:55 UTC Build successful.
🟢 2025-11-21 23:30:12 UTC ydbd size 3.8 GiB changed* by 0 Bytes, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 6a893e7	merge: fddcdb8	diff	diff %
ydbd size	4 109 043 864 Bytes	4 109 043 864 Bytes	0 Bytes	0.000%
ydbd stripped size	1 527 256 560 Bytes	1 527 256 560 Bytes	0 Bytes	0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

---

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