v0.2.8

docs/STORAGE_SEARCH_OPERATIONS.md

@@ -1,6 +1,6 @@
-# RustBox 0.2.6 storage/search operations
+# RustBox 0.2.8 storage/search operations
 
-RustBox 0.2.6 treats SQL, blob storage and search as independent capabilities. The database engine does not decide whether `data_dir` is allowed.
+RustBox 0.2.8 treats SQL, blob storage and search as independent capabilities. The database engine does not decide whether `data_dir` is allowed.
 
 ## Deployment matrix
 
@@ -50,6 +50,14 @@ The rebuild removes superseded outbox events older than the rebuild start and ke
 
 If `search.required=false`, an unavailable OpenSearch backend may leave the application usable while the outbox grows; readiness reports degraded search and workers retry later. With `search.required=true`, search health is a startup/readiness requirement.
 
+### Automatic body cache / deep index
+
+Automatic full-body caching is controlled by `search.deep_index`. When it is `true` and the search backend is enabled, every periodic IMAP reconciliation may fetch full MIME bodies for messages that have headers cached but no body/index yet. `sync.deep_index_batch_size` caps the number of bodies fetched in one pass. Full bodies are stored in the per-account application database/cache and then queued/indexed, so enabling this increases IMAP bandwidth, application-database/search-storage use and indexing CPU/I/O.
+
+`search.deep_index=false` is the production default. It prevents a server-wide forced full-mailbox download, but preserves the existing per-account `deep_index` opt-in. Development configuration sets `search.deep_index=true` so cache/index behavior is exercised without an additional preference change.
+
+`sync.interval_secs` controls the periodic reconciliation cadence. Active folders still use IMAP IDLE for near-real-time events; the periodic pass is the fallback/background reconciliation for counters, flags and headers in other folders and is also the cadence for automatic deep-index batches. Lower values converge faster but create more IMAP requests.
+
 ## Failure behavior
 
 - SQL unavailable: authoritative mailbox/session/account operations cannot proceed.