e52415f0e0
El SDK CI - dev / build-and-test (pull_request) Failing after 11m47s
The adaptive budget I added an hour ago could only grow, and grew toward a
share of TOTAL ram (80%, ~38 GiB on a 48 GB host). That is a memory leak with
extra steps: total never shrinks when other processes need memory, so the pool
had no way to notice it was starving the machine it runs on. Deployed briefly;
caught as memory pressure on the host.
A control loop with only one direction is not a control loop.
- pc_available_ram(): free + inactive + purgeable via host_statistics64 on
Darwin, MemAvailable on Linux. Availability is the quantity that moves when
the machine is under pressure; total is not. Returns 0 when it cannot be
read, and callers then refuse to grow — a cache is never worth swapping the
host, so unknown means no.
- Growth is bounded by availability minus a free-memory floor (2 GiB default,
ENGRAM_POOL_FREE_FLOOR_MB), not by total. The share-of-total ceiling stays
as a second bound and drops 80% -> 50%.
- pc_relieve_pressure(): the missing direction. On every eviction pass, if
available memory is under the floor, hand back ~25% of held frames; the
resident set follows on the next pass so the memory is actually returned
rather than merely re-labelled. Counted as adapt_shrinks alongside
adapt_grows so both directions are visible in the same report.
- pc_default_cap() also clamps the STARTING budget to what is spare right
now, so a cold boot on a loaded machine does not open at a size the host
cannot afford.
Verified on a 48 GB host: engram boots in ~30s, RSS settles at 2.22 GiB (the
store's actual size, resident, not creeping), 0.0% CPU, 13,439 nodes / 37,670
edges, embeddings complete. Guard reports 9.71 GiB available against a 2.00 GiB
floor — 7.71 GiB of headroom it is permitted to use and no more.