Scale Requirements

Part of: MPAC SmartPOS Cloud Platform - Product RequirementsVersion: 2.0 Last Updated: 2026-01-28

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Overview

This document defines the performance, capacity, and scalability requirements for the MPAC SmartPOS platform to support large-scale fleet operations.

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Capacity Requirements

Device Fleet

• Concurrent Devices: 400,000+ active SmartPOS terminals
• Device Connections: Persistent WebSocket connections for real-time sync
• Geographic Distribution: Multi-region deployment capability

Transaction Volume

• Daily Transactions: 80 million transactions per day
• Peak Throughput: 15,000 requests per second (RPS) sustained
• Average Transaction Size: ~2-5 KB payload
• Data Growth: ~50 TB/year transaction data

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Performance Targets

API Response Times

Operation Type	Target (P95)	Target (P99)
Authentication	< 200ms	< 500ms
Order Creation	< 300ms	< 800ms
Payment Processing	< 500ms	< 1000ms
Device Sync	< 200ms	< 500ms
Report Generation	< 2s	< 5s

Payment Gateway (mpac-pgw)

• P95 Latency: < 200ms
• P99 Latency: < 500ms
• Rate Limits:
  • 1,000 requests/min per merchant
  • 10,000 requests/min global
• Idempotency: 24-hour cache retention

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Availability & Reliability

Uptime SLA

• Target Availability: 99.9% uptime
• Maximum Downtime: 8.76 hours/year (43.8 minutes/month)
• Planned Maintenance: < 4 hours/quarter during off-peak

Disaster Recovery

• RTO (Recovery Time Objective): < 1 hour
• RPO (Recovery Point Objective): < 5 minutes
• Backup Frequency: Continuous replication + daily snapshots
• Multi-Region Failover: Automated with traffic routing

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Scalability Architecture

Horizontal Scaling

┌─────────────────────────────────────────────┐
│         Application Layer (Auto-scaling)     │
├─────────────┬─────────────┬─────────────────┤
│ svc-portal  │ svc-smarttab│    mpac-pgw      │
│  (2-20)     │   (5-50)    │    (3-30)       │
│  instances  │   instances │    instances    │
└─────────────┴─────────────┴─────────────────┘
         │              │              │
         └──────────────┴──────────────┘
                        │
         ┌──────────────▼──────────────┐
         │  Database Layer (Vertical)  │
         │  PostgreSQL Primary/Replica │
         │  + Redis Cluster            │
         └─────────────────────────────┘

Scaling Triggers

• CPU Utilization: Scale up at 70%, scale down at 30%
• Memory Utilization: Scale up at 80%
• Request Queue Depth: Scale up when > 1000 pending requests
• Response Time: Scale up when P95 latency > target + 50%

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Data Volume Projections

Year 1-2 (Current)

• Devices: 400K terminals
• Transactions: 80M/day (29B/year)
• Storage: ~50 TB active data
• Database Size: ~20 TB operational + 30 TB archive

Year 3-5 (Growth)

• Devices: 1M terminals (2.5x growth)
• Transactions: 200M/day (2.5x growth)
• Storage: ~125 TB active data
• Database Size: ~50 TB operational + 75 TB archive

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Multi-Tenancy Scale

Tenant Distribution

• PSPs: 10-50 active PSPs
• Merchants per PSP: 100-5,000 merchants
• Stores per Merchant: 1-1,000 stores
• Devices per Store: 1-50 terminals

Largest Tenants

• Single PSP: Up to 100,000 devices
• Single Merchant: Up to 10,000 devices
• Single Store: Up to 50 devices

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Network & Bandwidth

Bandwidth Requirements

• Peak Ingress: 500 Mbps (device → cloud)
• Peak Egress: 1 Gbps (cloud → device/portal)
• WebSocket Connections: 400K concurrent
• Average Connection Duration: 8 hours/day

CDN & Static Assets

• APK Distribution: 50-100 MB per app
• Monthly Downloads: ~100K app updates
• CDN Bandwidth: ~10 TB/month

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Monitoring & Observability

Metrics Collection

• Application Metrics: 1-minute granularity
• Infrastructure Metrics: 30-second granularity
• Logs: Centralized with 30-day retention
• Traces: Distributed tracing for 1% of requests

Performance Budget

• Total Observability Overhead: < 5% CPU/memory
• Log Volume: ~500 GB/day
• Metrics Cardinality: < 1M time series

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See Also

Related Documents:

• Product Overview - Platform capabilities
• System Architecture - High-level design
• Performance & Scalability - Technical implementation

Infrastructure:

• AWS Infrastructure - Cloud resources
• Deployment Strategy - Scaling procedures

Testing:

• Load Testing - Performance validation

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