The daemon keeps adjacency layers (store/graph_mem.h) resident across
requests -- 237 MB for the kernel -- with no end of life but LRU pressure.
- Idle eviction: a layer nobody has held for CBM_GRAPH_MEM_IDLE_EVICT_MS
(10 minutes, measured from its last release) is evicted on the next
request: cbm_mcp_handle_tool sweeps after releasing the request store, and
every acquire sweeps too. No timer thread. Ten minutes outlasts the gaps
between an agent's graph calls within one task, while a session that moved
on stops pinning the memory; a wrong guess costs one rebuild (1.2-1.5 s on
the 17 GB kernel index, tens of ms on ordinary repos). The clock is a test
seam (cbm_graph_mem_set_clock_for_testing), so tests move time instead of
waiting.
- Worker budget: application_worker_memory_slice_locked hands index workers
the aggregate minus the resident layer bytes (cbm_graph_mem_cached_bytes),
at least one byte per active job so a slice never reads as "no cap".
- Memory class: layers are charged to the new CBM_MEM_CLASS_GRAPH_CACHE
("graph_cache" in census and class logs) instead of STORE.
Responses stay byte-identical to the baseline on django and redis (tools
and Cypher) and on the kernel trace/hub and extra BFS/degree cases.
Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>
Martin Vogel
6bf6e34e43