feat: v3.10 GPU stress and NCCL burn updates

iso/overlay/usr/local/bin/bee-nccl-gpu-stress

@@ -0,0 +1,91 @@
+#!/bin/sh
+set -eu
+
+SECONDS=300
+DEVICES=""
+EXCLUDE=""
+MIN_BYTES="512M"
+MAX_BYTES="4G"
+FACTOR="2"
+ITERS="20"
+ALL_REDUCE_BIN="/usr/local/bin/all_reduce_perf"
+
+usage() {
+    echo "usage: $0 [--seconds N] [--devices 0,1] [--exclude 2,3]" >&2
+    exit 2
+}
+
+normalize_list() {
+    echo "${1:-}" | tr ',' '\n' | sed 's/[[:space:]]//g' | awk 'NF' | sort -n | uniq | paste -sd, -
+}
+
+contains_csv() {
+    needle="$1"
+    haystack="${2:-}"
+    echo ",${haystack}," | grep -q ",${needle},"
+}
+
+while [ "$#" -gt 0 ]; do
+    case "$1" in
+        --seconds|-t) [ "$#" -ge 2 ] || usage; SECONDS="$2"; shift 2 ;;
+        --devices) [ "$#" -ge 2 ] || usage; DEVICES="$2"; shift 2 ;;
+        --exclude) [ "$#" -ge 2 ] || usage; EXCLUDE="$2"; shift 2 ;;
+        *) usage ;;
+    esac
+done
+
+[ -x "${ALL_REDUCE_BIN}" ] || { echo "all_reduce_perf not found: ${ALL_REDUCE_BIN}" >&2; exit 1; }
+
+ALL_DEVICES=$(nvidia-smi --query-gpu=index --format=csv,noheader,nounits 2>/dev/null | sed 's/[[:space:]]//g' | awk 'NF' | paste -sd, -)
+[ -n "${ALL_DEVICES}" ] || { echo "nvidia-smi found no NVIDIA GPUs" >&2; exit 1; }
+
+DEVICES=$(normalize_list "${DEVICES}")
+EXCLUDE=$(normalize_list "${EXCLUDE}")
+SELECTED="${DEVICES}"
+if [ -z "${SELECTED}" ]; then
+    SELECTED="${ALL_DEVICES}"
+fi
+
+FINAL=""
+for id in $(echo "${SELECTED}" | tr ',' ' '); do
+    [ -n "${id}" ] || continue
+    if contains_csv "${id}" "${EXCLUDE}"; then
+        continue
+    fi
+    if [ -z "${FINAL}" ]; then
+        FINAL="${id}"
+    else
+        FINAL="${FINAL},${id}"
+    fi
+done
+
+[ -n "${FINAL}" ] || { echo "no NVIDIA GPUs selected after filters" >&2; exit 1; }
+
+GPU_COUNT=$(echo "${FINAL}" | tr ',' '\n' | awk 'NF' | wc -l | awk '{print $1}')
+[ "${GPU_COUNT}" -gt 0 ] || { echo "selected GPU count is zero" >&2; exit 1; }
+
+echo "loader=nccl"
+echo "selected_gpus=${FINAL}"
+echo "gpu_count=${GPU_COUNT}"
+echo "range=${MIN_BYTES}..${MAX_BYTES}"
+echo "iters=${ITERS}"
+
+deadline=$(( $(date +%s) + SECONDS ))
+round=0
+
+while :; do
+    now=$(date +%s)
+    if [ "${now}" -ge "${deadline}" ]; then
+        break
+    fi
+    round=$((round + 1))
+    remaining=$((deadline - now))
+    echo "round=${round} remaining_sec=${remaining}"
+    CUDA_VISIBLE_DEVICES="${FINAL}" \
+        "${ALL_REDUCE_BIN}" \
+        -b "${MIN_BYTES}" \
+        -e "${MAX_BYTES}" \
+        -f "${FACTOR}" \
+        -g "${GPU_COUNT}" \
+        --iters "${ITERS}"
+done