skkuding · tasoo-oos · May 26, 2026
diff --git a/tests/load/.env.example b/tests/load/.env.example
@@ -0,0 +1,14 @@
+BASE_URL=https://codedang.com/api
+USERNAME=
+PASSWORD=
+PROBLEM_ID=395
+
+# Reduced default load. Override as needed.
+NORMAL_VUS=20
+VILLAIN_VUS=2
+RAMP_UP_DURATION=30s
+STEADY_DURATION=2m
+RAMP_DOWN_DURATION=30s
+
+# Enable with: --out experimental-prometheus-rw
+# K6_PROMETHEUS_RW_SERVER_URL=https://prometheus.codedang.com/api/v1/write
diff --git a/tests/load/README.md b/tests/load/README.md
@@ -15,10 +15,12 @@ k6 (외부)
 
 | 시나리오 | VU | 설명 |
 |----------|---:|------|
-| `normal_users` | 140 | 언어별 정답 코드 제출 (A+B) |
-| `villain_users` | 10 | 자원 소모 악성 코드 제출 (무한루프, 메모리폭탄 등) |
+| `normal_users` | 20 | 언어별 정답 코드 제출 (A+B) |
+| `villain_users` | 2 | 자원 소모 악성 코드 제출 (무한루프, 메모리폭탄 등) |
 
-**단계**: 2분 ramp-up → 10분 steady → 2분 ramp-down (총 14분)
+**기본 단계**: 30초 ramp-up → 2분 steady → 30초 ramp-down (총 3분)
+
+VU 수와 시간은 `.env` 또는 `k6 run -e`로 조정할 수 있습니다.
 
 ## 사전 준비
 
@@ -29,16 +31,54 @@ k6 (외부)
 
 ## 실행
 
+로컬 설정 파일을 만듭니다. `.env`는 git에 커밋되지 않습니다.
+
 ```bash
 cd tests/load
+cp .env.example .env
+```
+
+`.env` 예시:
+
+```dotenv
+BASE_URL=https://codedang.com/api
+USERNAME=tasoo1118
+PASSWORD=your-password
+PROBLEM_ID=395
+
+NORMAL_VUS=20
+VILLAIN_VUS=2
+RAMP_UP_DURATION=30s
+STEADY_DURATION=2m
+RAMP_DOWN_DURATION=30s
+```
+
+실행:
+
+```bash
+cd tests/load
+k6 run \
+  --out "json=results/$(date +%Y%m%d-%H%M%S).json" \
+  submission-load.js
+```
+
+`-e`로 넘긴 값은 `.env`보다 우선합니다.
+
+```bash
+k6 run \
+  -e NORMAL_VUS=5 \
+  -e VILLAIN_VUS=0 \
+  -e STEADY_DURATION=30s \
+  --out "json=results/$(date +%Y%m%d-%H%M%S).json" \
+  submission-load.js
+```
+
+Prometheus remote write를 함께 사용할 때:
+
+```bash
 k6 run \
-  -e BASE_URL=https://codedang.com/api \
-  -e USERNAME=loadtest-user \
-  -e PASSWORD=your-password \
-  -e PROBLEM_ID=123 \
   --out experimental-prometheus-rw \
   --out "json=results/$(date +%Y%m%d-%H%M%S).json" \
-  -e K6_PROMETHEUS_RW_SERVER_URL=https://prometheus.codedang.com/api/v1/write \
   submission-load.js
 ```
 
@@ -60,6 +100,11 @@ k6 run \
 | `USERNAME` | O | 로그인 사용자명 |
 | `PASSWORD` | O | 로그인 비밀번호 |
 | `PROBLEM_ID` | O | 테스트 대상 문제 ID |
+| `NORMAL_VUS` | | 일반 사용자 VU 수 (기본: `20`) |
+| `VILLAIN_VUS` | | 악성 사용자 VU 수 (기본: `2`, `0`이면 비활성화) |
+| `RAMP_UP_DURATION` | | ramp-up 시간 (기본: `30s`) |
+| `STEADY_DURATION` | | steady 시간 (기본: `2m`) |
+| `RAMP_DOWN_DURATION` | | ramp-down 시간 (기본: `30s`) |
 | `K6_PROMETHEUS_RW_SERVER_URL` | | Prometheus remote write URL (`--out` 사용 시) |
 
 ## Grafana 대시보드 가이드

diff --git a/tests/load/submission-load.js b/tests/load/submission-load.js
@@ -8,18 +8,99 @@ const submissionErrors = new Counter('submission_errors')
 const submissionDuration = new Trend('submission_duration', true)
 
 // ── Environment variables ───────────────────────────────────────
-const BASE_URL = __ENV.BASE_URL || 'https://codedang.com/api'
-const USERNAME = __ENV.USERNAME
-const PASSWORD = __ENV.PASSWORD
-const PROBLEM_ID = __ENV.PROBLEM_ID
+function loadDotEnv() {
+  try {
+    return parseDotEnv(open('./.env'))
+  } catch (_) {
+    return {}
+  }
+}
+
+function parseDotEnv(content) {
+  const env = {}
+  for (const line of content.split(/\r?\n/)) {
+    const trimmed = line.trim()
+    if (!trimmed || trimmed.startsWith('#')) continue
+
+    const match = trimmed.match(/^([A-Za-z_][A-Za-z0-9_]*)\s*=\s*(.*)$/)
+    if (!match) continue
+
+    let value = match[2].trim()
+    if (
+      (value.startsWith('"') && value.endsWith('"')) ||
+      (value.startsWith("'") && value.endsWith("'"))
+    ) {
+      value = value.slice(1, -1)
+    }
+
+    env[match[1]] = value
+  }
+  return env
+}
+
+const dotenv = loadDotEnv()
+
+function env(name, fallback) {
+  const value = __ENV[name] !== undefined ? __ENV[name] : dotenv[name]
+  return value !== undefined && value !== '' ? value : fallback
+}
+
+function numberEnv(name, fallback) {
+  const value = Number(env(name, fallback))
+  if (!Number.isFinite(value) || value < 0) {
+    throw new Error(`${name} must be a non-negative number`)
+  }
+  return value
+}
+
+const BASE_URL = env('BASE_URL', 'https://codedang.com/api')
+const USERNAME = env('USERNAME')
+const PASSWORD = env('PASSWORD')
+const PROBLEM_ID = env('PROBLEM_ID')
+
+const NORMAL_VUS = numberEnv('NORMAL_VUS', 20)
+const VILLAIN_VUS = numberEnv('VILLAIN_VUS', 2)
+const RAMP_UP_DURATION = env('RAMP_UP_DURATION', '30s')
+const STEADY_DURATION = env('STEADY_DURATION', '2m')
+const RAMP_DOWN_DURATION = env('RAMP_DOWN_DURATION', '30s')
+
+if (NORMAL_VUS === 0 && VILLAIN_VUS === 0) {
+  throw new Error('At least one of NORMAL_VUS or VILLAIN_VUS must be greater than 0')
+}
 
 if (!USERNAME || !PASSWORD || !PROBLEM_ID) {
   throw new Error(
     'Required env vars: USERNAME, PASSWORD, PROBLEM_ID\n' +
-      'Usage: k6 run -e USERNAME=x -e PASSWORD=x -e PROBLEM_ID=123 submission-load.js'
+      'Usage: create .env or run k6 with -e USERNAME=x -e PASSWORD=x -e PROBLEM_ID=123 submission-load.js'
   )
 }
 
+function rampingScenario(exec, vus, tags) {
+  return {
+    executor: 'ramping-vus',
+    startVUs: 0,
+    stages: [
+      { duration: RAMP_UP_DURATION, target: vus },
+      { duration: STEADY_DURATION, target: vus },
+      { duration: RAMP_DOWN_DURATION, target: 0 }
+    ],
+    exec,
+    tags
+  }
+}
+
+const scenarios = {}
+if (NORMAL_VUS > 0) {
+  scenarios.normal_users = rampingScenario('normalSubmission', NORMAL_VUS, {
+    user_type: 'normal'
+  })
+}
+if (VILLAIN_VUS > 0) {
+  scenarios.villain_users = rampingScenario('villainSubmission', VILLAIN_VUS, {
+    user_type: 'villain'
+  })
+}
+
 // ── Payloads ────────────────────────────────────────────────────
 const normalPayloads = new SharedArray('normal', () => [
   { lang: 'C', code: open('./payloads/normal/solution.c') },
@@ -39,30 +120,7 @@ const villainPayloads = new SharedArray('villain', () => [
 
 // ── Scenarios ───────────────────────────────────────────────────
 export const options = {
-  scenarios: {
-    normal_users: {
-      executor: 'ramping-vus',
-      startVUs: 0,
-      stages: [
-        { duration: '2m', target: 140 },
-        { duration: '10m', target: 140 },
-        { duration: '2m', target: 0 }
-      ],
-      exec: 'normalSubmission',
-      tags: { user_type: 'normal' }
-    },
-    villain_users: {
-      executor: 'ramping-vus',
-      startVUs: 0,
-      stages: [
-        { duration: '2m', target: 10 },
-        { duration: '10m', target: 10 },
-        { duration: '2m', target: 0 }
-      ],
-      exec: 'villainSubmission',
-      tags: { user_type: 'villain' }
-    }
-  },
+  scenarios,
   thresholds: {
     http_req_duration: ['p(95)<5000'],
     submission_errors: ['count<50']