`cache/mod.rs` cache invalidation tags are not bounded — unbounded memory growth risk

[hman38705]

Labels: backend, reliability
Priority: Medium

Description

services/api/src/cache/mod.rs implements tag-based cache invalidation. If tags accumulate without TTL or size limits, the Redis memory usage can grow unboundedly, especially for high-cardinality tag sets.

Acceptance Criteria

• Tag sets stored with a TTL matching the longest-lived cached entry
• Tag set size capped; oldest entries evicted when cap is reached
• Redis memory usage for cache tags monitored via metrics

[Glittersup]

@Glittersup has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I’m interested in handling this issue. I’ve built and tested web3 applications across contracts, backend services, and frontend flows.

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[unrealtim-tech]

@unrealtim-tech has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi, I woould like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @unrealtim-tech to this issue.

[drips-wave]

Congratulations, @unrealtim-tech! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @unrealtim-tech: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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