​
Overview

The runMassSimulation function enables you to run multiple sessions in a batch for testing variations, performance analysis, or A/B testing scenarios.

​
Syntax

await lai.runMassSimulation(config: MassSimulationConfig): Promise<void>

​
Parameters

​
config
MassSimulationConfig
required
Configuration object with the following properties:

​
Returns

Returns a Promise that resolves when all simulation sessions are complete.

​
Examples

​
Basic Mass Simulation

await lai.runMassSimulation({
  sessionBaseName: "Performance Test",
  numSessions: 10,
  sessionFunction: async () => {
    // This function runs once and should create all sessions
    for (let i = 0; i < 10; i++) {
      await lai.initSession({
        sessionName: `Performance Test - ${i}`,
        tags: ["simulation", "performance"]
      });
      
      // Run your test scenario
      await runTestScenario(i);
      
      await lai.endSession(true);
    }
  }
});

​
A/B Testing Example

async function runABTest() {
  const variants = ['A', 'B'];
  const testCases = 20; // 10 per variant

  await lai.runMassSimulation({
    sessionBaseName: "Prompt A/B Test",
    numSessions: testCases,
    sessionFunction: async () => {
      for (let i = 0; i < testCases; i++) {
        const variant = variants[i % 2];
        
        await lai.initSession({
          sessionName: `Prompt A/B Test - ${i}`,
          tags: ["ab-test", `variant-${variant}`]
        });
        
        await lai.createStep({
          state: "Testing prompt variant",
          action: `Using variant ${variant}`
        });
        
        // Test different prompts
        const prompt = variant === 'A' 
          ? "Be concise and direct"
          : "Be detailed and explanatory";
          
        const result = await testPromptPerformance(prompt);
        
        await lai.endStep({
          evalScore: result.score,
          evalDescription: `Variant ${variant}: ${result.metric}`
        });
        
        await lai.endSession(true, `Completed variant ${variant} test`);
      }
    }
  });
}

​
Model Comparison

async function compareModels() {
  const models = ["gpt-3.5-turbo", "gpt-4", "gpt-4-turbo"];
  const testQueries = [
    "Explain quantum computing",
    "Write a haiku about AI",
    "Solve this math problem: 15% of 240"
  ];

  await lai.runMassSimulation({
    sessionBaseName: "Model Comparison",
    numSessions: models.length * testQueries.length,
    sessionFunction: async () => {
      const OpenAI = (await import('openai')).default;
      const openai = new OpenAI();
      
      for (const model of models) {
        for (const query of testQueries) {
          await lai.initSession({
            sessionName: `Model Comparison - ${model}`,
            tags: ["model-test", model, "comparison"]
          });
          
          await lai.createStep({
            state: `Testing ${model}`,
            action: `Query: ${query}`
          });
          
          const startTime = Date.now();
          
          const response = await openai.chat.completions.create({
            model,
            messages: [{ role: "user", content: query }]
          });
          
          const duration = Date.now() - startTime;
          
          await lai.endStep({
            evalScore: calculateQualityScore(response),
            evalDescription: `Response time: ${duration}ms`
          });
          
          await lai.endSession(true);
        }
      }
    }
  });
}

​
Parallel Execution Pattern

async function runParallelSimulation() {
  const concurrency = 5; // Run 5 sessions at a time
  const totalSessions = 50;

  await lai.runMassSimulation({
    sessionBaseName: "Parallel Load Test",
    numSessions: totalSessions,
    sessionFunction: async () => {
      // Create batches for parallel execution
      const batches = [];
      for (let i = 0; i < totalSessions; i += concurrency) {
        batches.push(
          Array.from({ length: Math.min(concurrency, totalSessions - i) }, 
            (_, j) => i + j
          )
        );
      }
      
      // Process batches
      for (const batch of batches) {
        await Promise.all(
          batch.map(async (sessionIndex) => {
            await lai.initSession({
              sessionName: `Parallel Load Test - ${sessionIndex}`
            });
            
            await simulateUserJourney(sessionIndex);
            
            await lai.endSession(true);
          })
        );
      }
    }
  });
}

​
Error Handling in Simulations

async function robustSimulation() {
  const scenarios = 20;
  const results = { success: 0, failed: 0 };

  await lai.runMassSimulation({
    sessionBaseName: "Reliability Test",
    numSessions: scenarios,
    sessionFunction: async () => {
      for (let i = 0; i < scenarios; i++) {
        try {
          await lai.initSession({
            sessionName: `Reliability Test - ${i}`
          });
          
          await lai.createStep({
            state: "Running scenario",
            action: `Scenario ${i}`
          });
          
          // Simulate random failures
          if (Math.random() > 0.8) {
            throw new Error("Simulated failure");
          }
          
          await performScenario(i);
          
          await lai.endStep({ evalScore: 100 });
          await lai.endSession(true);
          results.success++;
          
        } catch (error) {
          await lai.endStep({
            evalScore: 0,
            evalDescription: error.message
          });
          await lai.endSession(false, error.message);
          results.failed++;
        }
      }
      
      console.log(`Simulation complete: ${results.success} success, ${results.failed} failed`);
    }
  });
}

​
Common Patterns

​
1. Configuration Testing

async function testConfigurations() {
  const configs = [
    { temperature: 0.1, model: "gpt-3.5-turbo" },
    { temperature: 0.5, model: "gpt-3.5-turbo" },
    { temperature: 0.9, model: "gpt-3.5-turbo" },
    { temperature: 0.1, model: "gpt-4" },
    { temperature: 0.5, model: "gpt-4" },
    { temperature: 0.9, model: "gpt-4" }
  ];

  await lai.runMassSimulation({
    sessionBaseName: "Config Test",
    numSessions: configs.length,
    sessionFunction: async () => {
      for (const [index, config] of configs.entries()) {
        await lai.initSession({
          sessionName: `Config Test - ${index}`,
          tags: ["config-test", `temp-${config.temperature}`, config.model]
        });
        
        await testWithConfig(config);
        
        await lai.endSession(true);
      }
    }
  });
}

​
2. Time-based Testing

async function testAtDifferentTimes() {
  const timeSlots = 24; // Test every hour

  await lai.runMassSimulation({
    sessionBaseName: "24-Hour Test",
    numSessions: timeSlots,
    sessionFunction: async () => {
      for (let hour = 0; hour < timeSlots; hour++) {
        // Schedule for specific hour
        const scheduledTime = new Date();
        scheduledTime.setHours(hour, 0, 0, 0);
        
        // Wait until scheduled time
        const now = new Date();
        const delay = scheduledTime.getTime() - now.getTime();
        if (delay > 0) {
          await new Promise(resolve => setTimeout(resolve, delay));
        }
        
        await lai.initSession({
          sessionName: `24-Hour Test - ${hour}:00`,
          tags: ["time-test", `hour-${hour}`]
        });
        
        await runHourlyTest();
        
        await lai.endSession(true);
      }
    }
  });
}

​
Best Practices

​
1. Resource Management

// Don't overwhelm the system
const MAX_CONCURRENT = 10;
const semaphore = new Semaphore(MAX_CONCURRENT);

await lai.runMassSimulation({
  sessionBaseName: "Controlled Load",
  numSessions: 100,
  sessionFunction: async () => {
    const tasks = Array.from({ length: 100 }, async (_, i) => {
      await semaphore.acquire();
      try {
        await runSession(i);
      } finally {
        semaphore.release();
      }
    });
    
    await Promise.all(tasks);
  }
});

​
2. Meaningful Names and Tags

// Use descriptive naming for easy filtering
await lai.initSession({
  sessionName: `${baseName} - ${testType} - ${variant} - ${index}`,
  tags: [
    "simulation",
    `type:${testType}`,
    `variant:${variant}`,
    `batch:${batchId}`,
    `timestamp:${Date.now()}`
  ]
});

​
3. Progress Tracking

let completed = 0;
const total = 100;

await lai.runMassSimulation({
  sessionBaseName: "Progress Test",
  numSessions: total,
  sessionFunction: async () => {
    for (let i = 0; i < total; i++) {
      await runSingleSession(i);
      completed++;
      
      if (completed % 10 === 0) {
        console.log(`Progress: ${completed}/${total} (${(completed/total*100).toFixed(1)}%)`);
      }
    }
  }
});

​
Notes

  • The sessionFunction is called once and should handle all session creation
  • Each session within the simulation should be properly initialized and ended
  • Use tags to make filtering and analysis easier in the dashboard
  • Consider rate limits and resource constraints when running large simulations

​
See Also