stable-25-2: Optimized serialization in discovery cache cron job

[Gazizonoki]

Changelog entry

...

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

SPI-158207

[github-actions]

🟢 2025-10-01 12:46:20 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-09-30 14:57:59 UTC Pre-commit check linux-x86_64-release-asan for 016a595 has started.
⚪ 2025-09-30 14:59:00 UTC Artifacts will be uploaded here
⚪ 2025-09-30 15:02:38 UTC ya make is running...
🟡 2025-09-30 16:18:07 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
12821	12650	0	22	116	33

⚪ 2025-09-30 16:19:15 UTC ya make is running... (failed tests rerun, try 2)
🟡 2025-09-30 16:31:32 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet Going to retry failed tests...

Test history | Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
206 (only retried tests)	168	0	2	4	32

⚪ 2025-09-30 16:31:41 UTC ya make is running... (failed tests rerun, try 3)
🟢 2025-09-30 16:44:24 UTC Tests successful.

Test history | Ya make output | Test bloat | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
67 (only retried tests)	34	0	0	4	29

🟢 2025-09-30 16:44:32 UTC Build successful.
🟢 2025-09-30 16:44:56 UTC ydbd size 3.8 GiB changed* by +2.9 KiB, which is < 100.0 KiB vs stable-25-2: OK

ydbd size dash	stable-25-2: 4030585	merge: 016a595	diff	diff %
ydbd size	4 049 129 088 Bytes	4 049 132 080 Bytes	+2.9 KiB	+0.000%
ydbd stripped size	1 409 362 104 Bytes	1 409 363 192 Bytes	+1.1 KiB	+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]

⚪ 2025-09-30 15:17:18 UTC Pre-commit check linux-x86_64-relwithdebinfo for 016a595 has started.
⚪ 2025-09-30 15:17:50 UTC Artifacts will be uploaded here
⚪ 2025-09-30 15:21:20 UTC ya make is running...
🟢 2025-09-30 16:14:11 UTC Tests successful.

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
27008	25724	0	0	1238	46

🟢 2025-09-30 16:16:40 UTC Build successful.
🟢 2025-09-30 16:16:54 UTC ydbd size 2.2 GiB changed* by +896 Bytes, which is < 100.0 KiB vs stable-25-2: OK

ydbd size dash	stable-25-2: 4030585	merge: 016a595	diff	diff %
ydbd size	2 326 580 192 Bytes	2 326 581 088 Bytes	+896 Bytes	+0.000%
ydbd stripped size	487 499 752 Bytes	487 499 944 Bytes	+192 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}