dtoro
a4ea542f3e
Fix 3 of plans/2026-07-11-concurrent-task-execution.md, the throughput one. nomos held exactly one *mcpClient for the whole process, shared by every /chat goroutine. Its mutex was held for the full duration of each tool round-trip, and `run` executes its SSH command SYNCHRONOUSLY inside that round-trip (capped at up to 10 minutes) — so while Task A was mid-`run`, every other task's tool calls, even a trivial get_entity, queued behind that single lock. Tasks could think (LLM calls) in parallel but never act in parallel. The MCP server has no per-connection state to protect (newServer returns one shared *mcp.Server instance whose handlers close only over the DB connection pool, already safe for concurrent use) — the mutex existed purely because the client reused one stateful transport session. So the fix doesn't touch the server at all: - New mcpClientPool (cmd/nomos/main.go): one *mcpClient per session id, created lazily (a real MCP initialize handshake) on first use and cached; session-less traffic (the ephemeral no-DB-store path, the structured /query endpoint) gets its own fixed, reused key instead of a fresh connection per request. Idle clients (20 min past last use — long enough to outlive a single slow `run`) are evicted on a 5-minute sweep ticker. - agent.go: `client *mcpClient` → `clients *mcpClientPool`; every call site (buildTools, fleetSnapshot, the tool-dispatch loop) now resolves its own session's client via clients.get(sessionID) instead of reaching for one shared field. A task's own tool calls stay sequential (already true — the agent loop calls tools one at a time within a turn) but no longer block anyone else's. - main.go: handleQuery takes the pool instead of a client (keyed "query", a fixed non-session slot); shutdown calls pool.closeAll(). Verified live against the deployed stack: fired a slow-but-ungated command (`ping -c 15 127.0.0.1`, read-only per policy's allowlist, no approval needed) as Task A, then — 2s into A's run — a trivial hostname lookup as Task B, both through the real /chat endpoint. Task A's ping genuinely ran ~14.3s (confirmed via its own execution record and the agent's reported output). Task B returned in 6s total, well before A finished — proving it was never queued behind A's connection. Before this fix, B would have been forced to wait out A's entire ~14.3s hold on the single shared client. This completes plans/2026-07-11-concurrent-task-execution.md's required scope — only the explicitly optional/deferred Fix 4 (a concurrency/cost cap, pending real usage data) remains. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
26 KiB
26 KiB