CRITICAL fix: use async save_session to avoid blocking tokio runtime#534
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skymoore wants to merge 2 commits intoRightNow-AI:mainfrom
Open
CRITICAL fix: use async save_session to avoid blocking tokio runtime#534skymoore wants to merge 2 commits intoRightNow-AI:mainfrom
skymoore wants to merge 2 commits intoRightNow-AI:mainfrom
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This was referenced Mar 12, 2026
save_session() was synchronous, holding a Mutex<Connection> on the tokio worker thread during SQLite writes. On pods with 1 CPU core (1 tokio worker thread), this starved the entire runtime — including health check endpoints — causing K8s to mark the pod not-ready and return 504 on all subsequent requests. Add save_session_async() that wraps the SQLite write in spawn_blocking, matching the pattern already used by other memory operations (recall, remember, etc.). Update all 12 call sites in the agent loop.
The health endpoint called structured_get() synchronously on the tokio async runtime, acquiring the shared std::sync::Mutex<Connection> on a worker thread. When the agent loop held this mutex during session saves, the health check blocked the tokio thread, starving the SSE stream and causing Kubernetes probe timeouts. - Health and health_detail now run the DB check via spawn_blocking - SSE message/stream endpoint now includes keep_alive to flush periodic heartbeats even during contention
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Summary
Prevents 1 cpu openfang deployments from hanging on save session and not responding to any requests
Changes
save_session() was synchronous, holding a Mutex on the tokio worker thread during SQLite writes. On pods with 1 CPU core (1 tokio worker thread), this starved the entire runtime — including health check endpoints — causing K8s to mark the pod not-ready and return 504 on all subsequent requests.
Add save_session_async() that wraps the SQLite write in spawn_blocking, matching the pattern already used by other memory operations (recall, remember, etc.). Update all 12 call sites in the agent loop.
Testing
cargo clippy --workspace --all-targets -- -D warningspassescargo test --workspacepassesSecurity