Lambda Performance MCP Server

Instructions

Implementation Reference

• src/lambda-analyzer.js:166-203 (handler)

  Core handler implementing the memory utilization analysis, fetching config, logs, calculating stats, and generating recommendations.

  async analyzeMemoryUtilization(functionName, timeRange) {
    const timeRangeMs = this.parseTimeRange(timeRange);
    const endTime = new Date();
    const startTime = new Date(endTime.getTime() - timeRangeMs);
  
    // Get function configuration
    const config = await this.getFunctionConfig(functionName);
    const allocatedMemory = config.MemorySize;
  
    // Get memory usage from logs
    const memoryUsage = await this.getMemoryUsageFromLogs(functionName, startTime, endTime);
    
    const avgUsed = memoryUsage.reduce((sum, usage) => sum + usage, 0) / memoryUsage.length || 0;
    const peakUsed = Math.max(...memoryUsage, 0);
    const minUsed = Math.min(...memoryUsage, allocatedMemory);
    const utilizationPercent = Math.round((avgUsed / allocatedMemory) * 100);
  
    // Generate recommendation
    const recommendation = this.generateMemoryRecommendation(
      allocatedMemory, 
      avgUsed, 
      peakUsed, 
      utilizationPercent
    );
  
    return {
      allocated: allocatedMemory,
      avgUsed: Math.round(avgUsed),
      peakUsed: Math.round(peakUsed),
      minUsed: Math.round(minUsed),
      utilizationPercent,
      recommended: recommendation.memory,
      reasoning: recommendation.reasoning,
      performanceImpact: recommendation.performanceImpact,
      costImpact: recommendation.costImpact,
      patterns: this.analyzeMemoryPatterns(memoryUsage)
    };
  }

• index.js:410-438 (handler)

  MCP server handler wrapper that invokes the analyzer and formats the response for the MCP protocol.

  async analyzeMemoryUtilization(args) {
    const { functionName, timeRange = '24h' } = args;
    
    const memoryAnalysis = await this.lambdaAnalyzer.analyzeMemoryUtilization(
      functionName, 
      timeRange
    );
  
    return {
      content: [
        {
          type: 'text',
          text: `# Memory Utilization Analysis: ${functionName}\n\n` +
                `## Current Configuration\n` +
                `- **Allocated Memory**: ${memoryAnalysis.allocated}MB\n` +
                `- **Average Used**: ${memoryAnalysis.avgUsed}MB (${memoryAnalysis.utilizationPercent}%)\n` +
                `- **Peak Usage**: ${memoryAnalysis.peakUsed}MB\n` +
                `- **Minimum Usage**: ${memoryAnalysis.minUsed}MB\n\n` +
                `## Right-sizing Recommendation\n` +
                `- **Recommended Memory**: ${memoryAnalysis.recommended}MB\n` +
                `- **Reasoning**: ${memoryAnalysis.reasoning}\n` +
                `- **Expected Performance Impact**: ${memoryAnalysis.performanceImpact}\n` +
                `- **Cost Impact**: ${memoryAnalysis.costImpact}\n\n` +
                `## Memory Usage Patterns\n` +
                `${memoryAnalysis.patterns.map(pattern => `- ${pattern}`).join('\n')}`
        }
      ]
    };
  }

• index.js:148-164 (registration)

  Tool registration in the MCP server's listTools response, including name, description, and input schema.

  name: 'analyze_memory_utilization',
  description: 'Analyze memory utilization and provide right-sizing recommendations',
  inputSchema: {
    type: 'object',
    properties: {
      functionName: {
        type: 'string',
        description: 'Name of the Lambda function'
      },
      timeRange: {
        type: 'string',
        enum: ['1h', '6h', '24h', '7d'],
        description: 'Time range for memory analysis (default: 24h)'
      }
    },
    required: ['functionName']
  }

• src/lambda-analyzer.js:447-474 (helper)

  Helper method that generates memory right-sizing recommendations based on utilization stats.

  generateMemoryRecommendation(allocated, avgUsed, peakUsed, utilizationPercent) {
    let recommendedMemory = allocated;
    let reasoning = '';
    let performanceImpact = 'No change expected';
    let costImpact = 'No change';
  
    if (utilizationPercent < 50) {
      // Over-provisioned
      recommendedMemory = Math.max(128, Math.ceil(peakUsed * 1.2 / 64) * 64);
      reasoning = 'Memory is over-provisioned. Reducing memory will lower costs.';
      costImpact = `Reduce costs by ~${Math.round((1 - recommendedMemory/allocated) * 100)}%`;
      performanceImpact = 'Minimal performance impact expected';
    } else if (utilizationPercent > 85) {
      // Under-provisioned
      recommendedMemory = Math.ceil(peakUsed * 1.3 / 64) * 64;
      reasoning = 'Memory utilization is high. Increasing memory may improve performance.';
      costImpact = `Increase costs by ~${Math.round((recommendedMemory/allocated - 1) * 100)}%`;
      performanceImpact = 'Improved performance and reduced duration expected';
    } else {
      reasoning = 'Memory allocation appears optimal for current usage patterns.';
    }
  
    return {
      memory: recommendedMemory,
      reasoning,
      performanceImpact,
      costImpact
    };

• src/lambda-analyzer.js:544-547 (helper)

  Helper to fetch memory usage data from CloudWatch logs (placeholder implementation).

  async getMemoryUsageFromLogs(functionName, startTime, endTime) {
    // Placeholder implementation - would parse CloudWatch logs for memory usage
    return Array.from({ length: 100 }, () => Math.floor(Math.random() * 200) + 100);
  }