Feat/memory optimize for sync molnix

[thenav56]

Addresses

• Molnix provisioning issue in k8s

Changes

• Replace normal array with generator to limit memory usages
• Lower the kube cronjob memory requirement

Note

This is not the best approach, but it keeps the changes small to avoid unexpected breaking changes.

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Headline numbers

Replay A/B (memray-instrumented, two DBs, simultaneous) and live A/B (real Molnix API, two DBs, simultaneous)

Metric	Baseline (measured)	Modified (measured)	Δ (measured)	Remark
Peak RAM (replay, memray)	6.035 GB	560.3 MB	−91 %, ~11× smaller	Cleanest A/B since memray reads the actual heap. The ratio is what matters; absolute numbers include some fixture-loader overhead in both.
Peak RAM (live, docker stats RSS)	~5.60 GiB (observed)	~360 MiB (observed)	~16× smaller	docker stats samples once per ~60 s so it can miss a brief spike, but the trend across many samples is consistent.
Total allocations (replay)	10,908,529	14,304,384	+31 %	Modified has more small allocs because each record goes through json.dumps/loads extra times when cached.
Total bytes allocated, sum over time (replay)	117.9 GB	152.6 GB	+29 %	Sum-over-time inflated by the fixture loader's per-page rescans; production would be much smaller.
Max single allocation (replay)	3.845 MB	3.845 MB	unchanged	One JSON page worth — same either way.
Runtime (local cache only, no Molnix calls)	91 s	134 s	+47 %	Replay-only timing: no network at all, both runs read JSONL fixture files from local disk. The gap is the pure cost of _CachedPaginated's write+read tee with everything else being microseconds. In production the cache write happens during the network read, so its cost overlaps with network wait.
Runtime (live Molnix API)	2196 s (36m 36s)	2215 s (36m 55s)	+19 s (+0.9 %)	Within noise. Confirms the prediction: when network round-trips dominate the run, the cache I/O is invisible.

Re-iteration counts (_CachedPaginated)

Each _CachedPaginated.__iter__ call emits a log.warning with a counter. The counts below are measured from log output of a replay run — first iteration streams from source (writes JSONL cache to /tmp/); subsequent iterations replay from the cache.

Example log output from a verification replay:

WARNING  _CachedPaginated[deployments] first iteration #1 streaming from source -> /tmp/molnix_paginated_xxx.jsonl
WARNING  _CachedPaginated[positions]   first iteration #1 streaming from source -> /tmp/molnix_paginated_yyy.jsonl
WARNING  _CachedPaginated[positions]   re-iteration #2 from cache /tmp/molnix_paginated_yyy.jsonl
WARNING  _CachedPaginated[positions]   re-iteration #3 from cache /tmp/molnix_paginated_yyy.jsonl
WARNING  _CachedPaginated[deployments] re-iteration #2 from cache /tmp/molnix_paginated_xxx.jsonl
WARNING  _CachedPaginated[deployments] re-iteration #3 from cache /tmp/molnix_paginated_xxx.jsonl
WARNING  _CachedPaginated[deployments] re-iteration #4 from cache /tmp/molnix_paginated_xxx.jsonl

Wrapper	First iteration (from API)	Re-iterations (from cache)	Total __iter__ calls	Call sites in sync_molnix.py
_CachedPaginated[deployments]	1	3	4	get_unique_tags (L78) → [d["id"] for d in ...] (L260) → [get_go_event(d["tags"]) for d in ...] (L266) → for md in molnix_deployments: (L295)
_CachedPaginated[positions]	1	2	3	get_unique_tags (L83) → [p["id"] for p in ...] (L462) → for position in molnix_positions: (L468)
Total	2	5	7

With the cache, each re-iteration is a sequential read of a /tmp/molnix_paginated_*.jsonl file (deployments ~734 MB, positions ~890 MB).

[thenav56]

Hey @szabozoltan69, When you have time, let's merge and deploy to staging if we will not have a live release soon from staging.

It would be nice to test this in staging for few days.

[szabozoltan69]

Thanks so much @thenav56 for this great and gap filling fix! I deploy it to Staging now.

[szabozoltan69]

Deployed to Staging.