🏗️ Architecture

CoreSystem.Cache.Rehydration coordinates recovery between the memory fallback and the primary cache provider.

Rehydration Flow

Core.Cache
    │
    ├── Primary provider
    │
    └── Memory fallback
          │
          │ CacheEntryOptions.Rehydrate
          ▼
    ICacheKeyTracker
          │
          ▼
MemoryRehydrationSource
          │
          ▼
RehydrationService
          │
          │ Primary health = Healthy
          ▼
CacheRehydrator
          │
          ▼
PrimaryRehydrationTarget
          │
          ▼
ICacheStorageResolver.Primary

Source

MemoryRehydrationSource reads tracked keys from memory and creates CacheRehydrationEntry objects containing:

• key;
• value;
• remaining expiration;
• tags.

Expired entries are ignored.

Target

PrimaryRehydrationTarget writes each entry to the current primary storage, preserving its remaining expiration and tags.

Recovery Detection

RehydrationService executes a health-check cycle and considers the primary healthy only when at least one health check tagged primary exists and all such checks report Healthy.

Rehydration starts only after the service has previously observed the primary as unhealthy and then observes it as healthy.

Background Processing

RehydrationBackgroundService executes the recovery cycle repeatedly using the configured interval.

CacheRehydrator processes entries in batches of 100 and waits 100 ms between batches. A failed entry is logged and remains available for a later attempt.