Proposed Changes

It was observed that rabbit_core_metrics_gc and rabbit_stream_metrics_gc processes can grow to several MBs of memory (probably because fetching the list of all queues). As they execute infrequently (every 2 minutes by default) it can save some memory to hibernate them in-between (similar to other similar processes).

On an idle test server with 30K queues the rabbit_core_metrics_gc process consumed ~50MB memory.

This is an ad-hoc optimisation (low-hanging fruit) mostly to follow good practice of hibernating similar processes.

Types of Changes

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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

Checklist

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Further Comments

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This is an automatic backport of pull request #12149 done by [Mergify](https://mergify.com).

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This is an automatic backport of pull request #12150 done by [Mergify](https://mergify.com).