Description

This PR implements gzip compression for large cache entries to significantly reduce memory footprint in the cache service.

Problem

Cache entries for large debug queries (30+ MB JSON responses) were consuming excessive memory, leading to potential OOM issues in high-throughput scenarios.

Solution

• Automatically compress cache responses larger than 1MB using gzip
• Transparently decompress on cache retrieval
• Track compression status with IsCompressed flag in CacheValue
• JSON responses typically achieve 70-90% compression (tested at 99.53% for realistic payloads)

Changes

• ecosystem/cache/handlers.go:

  • Added CompressionThreshold constant (1MB)
  • Added IsCompressed field to CacheValue struct
  • Implemented compressData() and decompressData() helper functions
  • Modified formatCacheValue() to compress large responses
  • Modified ToCacheReply() to automatically decompress on retrieval
  • Updated Cost() to reflect actual stored size (compressed if applicable)

• ecosystem/cache/handlers_test.go (new file):

  • Comprehensive test suite with 21 subtests covering:
    • Compress/decompress roundtrip verification
    • Error handling for invalid gzip data
    • Threshold-based compression logic
    • Automatic decompression on retrieval
    • Memory cost calculation
    • Real-world compression ratio validation (99.53% for repeated JSON)

Impact

• Memory savings: 70-90% reduction for large JSON responses
• No API changes: Compression/decompression is transparent
• Performance: Minimal CPU overhead (gzip is highly optimized for JSON)
• Backward compatible: Existing cache entries continue to work

Closes: #XXXX

Author Checklist

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please add links to any relevant follow up issues.

I have...

• read the contribution guide
• included the correct type prefix in the PR title (perf)
• confirmed ! in the type prefix if API or client breaking change (N/A - no breaking changes)
• targeted the main branch
• provided a link to the relevant issue or specification
• reviewed "Files changed" and left comments if necessary
• included the necessary unit and integration tests (comprehensive test suite with 21 subtests)
• updated the relevant documentation or specification, including comments for documenting Go code
• confirmed all CI checks have passed

Reviewers Checklist

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I have...

• confirmed the correct type prefix in the PR title
• confirmed all author checklist items have been addressed
• reviewed state machine logic, API design and naming, documentation is accurate, tests and test coverage