#!/usr/bin/env bash
# Launch ERP-seat SFT run 7 on pfi-gx10 (NVIDIA GB10, aarch64, sm_121).
#
# Run this ON pfi-gx10 as infra-ops. It detaches the job from the invoking
# shell and logs to the box, so a reaped SSH session cannot take the run with
# it -- the failure mode that lost the first probe launch on 2026-09-01.
#
# Run 6 = run 5 recipe UNCHANGED on the jenerallee78 ARA-abliterated base (the single variable).
# 8,505 survivors -> ~543 optimizer steps; held targets must match run 6, slot adds 293 records.
# Checkpoints every 50 steps.
set -euo pipefail

ROOT=/home/infra-ops/erp-tune
HARNESS=$ROOT/eitri-smithy
VENV=/home/infra-ops/ml/.venv/bin/python
CONFIG=$ROOT/run-07-gx10.json
LOG=$ROOT/run-07.log

# --- Preconditions, asserted rather than assumed -----------------------------

# A stuck orphan holding unified memory while PyTorch reports zero allocated
# already doomed three relaunches on this box and got blamed on the new run
# each time. Assert the GPU is clear.
apps=$(nvidia-smi --query-compute-apps=pid --format=csv,noheader | tr -d '[:space:]')
if [ -n "$apps" ]; then
  echo "REFUSING: GPU is not clear -- compute apps still resident:" >&2
  nvidia-smi --query-compute-apps=pid,process_name,used_memory --format=csv >&2
  exit 1
fi

# Deliberately NOT `pgrep -f erp_sft_harness`: run this over ssh and the
# pattern appears in the invoking shell's own argv, so the guard matches
# itself and refuses every launch. The pidfile is exact and cannot self-match;
# the GPU assertion above catches an orphan under any name.
if [ -f "$ROOT/run-07.pid" ] && kill -0 "$(cat "$ROOT/run-07.pid")" 2>/dev/null; then
  echo "REFUSING: run-07.pid names a live process $(cat "$ROOT/run-07.pid"):" >&2
  ps -p "$(cat "$ROOT/run-07.pid")" -o pid,etime,cmd >&2
  exit 1
fi

if [ -e "$LOG" ]; then
  echo "REFUSING: $LOG exists. Move it aside first so two runs cannot share a log." >&2
  exit 1
fi

for p in "$HARNESS/erp_sft_harness/__main__.py" "$VENV" "$CONFIG"; do
  [ -e "$p" ] || { echo "REFUSING: missing $p" >&2; exit 1; }
done

# Free space for checkpoints, with headroom.
avail=$(df --output=avail -BG "$ROOT" | tail -1 | tr -dc '0-9')
if [ "$avail" -lt 40 ]; then
  echo "REFUSING: only ${avail}G free under $ROOT; want >=40G for checkpoints." >&2
  exit 1
fi

# --- Launch ------------------------------------------------------------------

cd "$HARNESS"
{
  echo "# launched $(date -Is) on $(hostname) by ${USER}"
  echo "# harness $(git rev-parse --short HEAD) config $CONFIG"
} > "$LOG"

setsid nohup "$VENV" -m erp_sft_harness --config "$CONFIG" >> "$LOG" 2>&1 < /dev/null &
pid=$!
echo "$pid" > "$ROOT/run-07.pid"

echo "launched pid $pid -> $LOG"
echo
echo "watch:   tail -f $LOG | tr '\\r' '\\n'"
echo "stop:    kill \$(cat $ROOT/run-07.pid)      # by PID -- never pkill -f over ssh"