Initial import

2026-07-04 20:44:28 +02:00
commit b3ae18d911
7 changed files with 456 additions and 0 deletions
@@ -0,0 +1,144 @@
+#!/bin/sh
+# Reproducible local performance proof for lines.
+# req: performance/002
+# req: performance/003
+# req: verification/003
+
+set -eu
+
+bin=${1:-zig-out/bin/lines}
+line_count=${LINES_PERF_LINES:-10000000}
+tmp=${TMPDIR:-/tmp}/lines-perf.$$
+data=$tmp.data
+trap 'rm -f "$tmp".*' EXIT HUP INT TERM
+
+case $line_count in
+    ''|*[!0-9]*) echo 'perf: LINES_PERF_LINES must be a positive decimal integer' >&2; exit 2 ;;
+esac
+if [ "$line_count" -eq 0 ]; then
+    echo 'perf: LINES_PERF_LINES must be greater than zero' >&2
+    exit 2
+fi
+if [ "$line_count" -lt 10000000 ] && [ "${LINES_PERF_ALLOW_SMALL:-0}" != 1 ]; then
+    echo 'perf: set LINES_PERF_ALLOW_SMALL=1 for a non-requirement quick run' >&2
+    exit 2
+fi
+
+if [ ! -x "$bin" ]; then
+    echo "perf: executable not found: $bin" >&2
+    exit 2
+fi
+
+now_ns() {
+    ns=$(date +%s%N 2>/dev/null || true)
+    case $ns in
+        *[!0-9]*|'') printf '%s000000000\n' "$(date +%s)" ;;
+        *) printf '%s\n' "$ns" ;;
+    esac
+}
+
+measure_proc() {
+    label=$1
+    shift
+    start_ns=$(now_ns)
+    "$@" >/dev/null &
+    pid=$!
+    peak_kb=0
+    while kill -0 "$pid" 2>/dev/null; do
+        rss_kb=$(awk '/^VmRSS:/ { print $2; found = 1; exit } END { if (!found) print 0 }' "/proc/$pid/status" 2>/dev/null || printf '0\n')
+        if [ "$rss_kb" -gt "$peak_kb" ]; then
+            peak_kb=$rss_kb
+        fi
+        sleep 0.01 2>/dev/null || sleep 1
+    done
+    wait "$pid"
+    end_ns=$(now_ns)
+    elapsed=$(awk -v start="$start_ns" -v end="$end_ns" 'BEGIN { printf "%.3f", (end - start) / 1000000000 }')
+    printf '%s\t%s\t%s\n' "$label" "$elapsed" "$peak_kb"
+}
+
+measure_time() {
+    label=$1
+    shift
+    metrics=$tmp.$label.time
+    case $time_mode in
+        gnu)
+            "$time_bin" -f '%e\t%M' -o "$metrics" "$@" >/dev/null
+            elapsed=$(awk 'BEGIN { FS = "\t" } { print $1; exit }' "$metrics")
+            rss_kb=$(awk 'BEGIN { FS = "\t" } { print $2; exit }' "$metrics")
+            ;;
+        bsd)
+            "$time_bin" -l -o "$metrics" "$@" >/dev/null
+            elapsed=$(awk '/ real$/ { print $1; exit }' "$metrics")
+            rss_bytes=$(awk '/maximum resident set size/ { print $1; exit }' "$metrics")
+            rss_kb=$(awk -v bytes="$rss_bytes" 'BEGIN { printf "%.0f", (bytes + 1023) / 1024 }')
+            ;;
+    esac
+    printf '%s\t%s\t%s\n' "$label" "$elapsed" "$rss_kb"
+}
+
+measure() {
+    case $measure_mode in
+        time) measure_time "$@" ;;
+        proc) measure_proc "$@" ;;
+    esac
+}
+
+measure_mode=
+for candidate in /usr/bin/time /bin/time gtime; do
+    if command -v "$candidate" >/dev/null 2>&1; then
+        if "$candidate" -f '%e\t%M' -o "$tmp.probe" true 2>/dev/null; then
+            time_bin=$candidate
+            time_mode=gnu
+            measure_mode=time
+            break
+        fi
+        if "$candidate" -l -o "$tmp.probe" true 2>/dev/null; then
+            time_bin=$candidate
+            time_mode=bsd
+            measure_mode=time
+            break
+        fi
+    fi
+done
+if [ -z "$measure_mode" ]; then
+    if [ -r /proc/$$/status ]; then
+        measure_mode=proc
+    else
+        echo 'perf: peak RSS needs GNU/BSD time or Linux /proc status sampling' >&2
+        exit 2
+    fi
+fi
+
+start=$((line_count - 99))
+end=$line_count
+
+printf 'perf: generating %s lines in %s\n' "$line_count" "$data" >&2
+awk -v n="$line_count" 'BEGIN { for (i = 1; i <= n; i++) printf "%08d abcdefghijklmnopqrstuvwxyz\n", i }' > "$data"
+actual_lines=$(wc -l < "$data" | tr -d ' ')
+bytes=$(wc -c < "$data" | tr -d ' ')
+if [ "$actual_lines" -ne "$line_count" ]; then
+    echo "perf: generated $actual_lines lines, expected $line_count" >&2
+    exit 1
+fi
+
+printf 'tool\telapsed_seconds\tpeak_rss_kb\tlines\tbytes\tstart\tend\tcommand\n'
+lines_row=$(measure lines "$bin" "$data" "$start" "$end")
+sed_row=$(measure sed sed -n "${start},${end}p" "$data")
+
+lines_elapsed=$(printf '%s\n' "$lines_row" | awk 'BEGIN { FS = "\t" } { print $2 }')
+lines_rss=$(printf '%s\n' "$lines_row" | awk 'BEGIN { FS = "\t" } { print $3 }')
+sed_elapsed=$(printf '%s\n' "$sed_row" | awk 'BEGIN { FS = "\t" } { print $2 }')
+sed_rss=$(printf '%s\n' "$sed_row" | awk 'BEGIN { FS = "\t" } { print $3 }')
+
+printf '%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s %s %s %s\n' lines "$lines_elapsed" "$lines_rss" "$line_count" "$bytes" "$start" "$end" "$bin" "$data" "$start" "$end"
+printf '%s\t%s\t%s\t%s\t%s\t%s\t%s\tsed -n %s,%sp %s\n' sed "$sed_elapsed" "$sed_rss" "$line_count" "$bytes" "$start" "$end" "$start" "$end" "$data"
+
+awk -v le="$lines_elapsed" -v se="$sed_elapsed" 'BEGIN { if (se <= 0 || le > se * 2.0) exit 1 }' || {
+    echo "perf: lines elapsed ${lines_elapsed}s is not within 2x sed ${sed_elapsed}s" >&2
+    exit 1
+}
+awk -v lr="$lines_rss" -v sr="$sed_rss" 'BEGIN { if (sr > 0 && lr > sr * 2.0) exit 1 }' || {
+    echo "perf: lines RSS ${lines_rss} KiB is not within 2x sed ${sed_rss} KiB" >&2
+    exit 1
+}