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Performance — v2.1.0

Dataset: 28,014 packets, ~650 nodes, 2 observers
Hardware: ARM64 (MikroTik CCR2116), single-core Node.js

A/B Benchmark: v2.0.1 (before) vs v2.1.0 (after)

All times are averages over 3 runs. "Cached" = warm TTL cache hit.

Endpoint v2.0.1 v2.1.0 (cold) v2.1.0 (cached) Speedup
Bulk Health 7,059 ms 3 ms 1 ms 7,059×
Node Analytics 381 ms 2 ms 1 ms 381×
Hash Sizes 353 ms 193 ms 1 ms 353×
Topology 685 ms 579 ms 2 ms 342×
RF Analytics 253 ms 235 ms 1 ms 253×
Channels 206 ms 77 ms 1 ms 206×
Node Health 195 ms 1 ms 1 ms 195×
Node Detail 133 ms 1 ms 1 ms 133×
Channel Analytics 95 ms 73 ms 2 ms 47×
Packets (grouped) 76 ms 33 ms 28 ms 2×
Stats 2 ms 1 ms 1 ms 2×
Nodes List 3 ms 2 ms 2 ms 1×
Observers 1 ms 8 ms 1 ms 1×

Architecture

Two-Layer Performance Stack

  1. In-Memory Packet Store (packet-store.js)

    • All packets loaded from SQLite into RAM on startup (~28K packets = ~12MB)
    • Indexed by id, hash, observer, and node (Map-based O(1) lookup)
    • Ring buffer with configurable max memory (default 1GB, ~2.3M packets)
    • SQLite becomes write-only for packets — reads never touch disk
    • New packets from MQTT written to both RAM + SQLite

  2. TTL Cache (server.js)

    • Computed API responses cached with configurable TTLs (via config.json)
    • Smart invalidation: packet bursts only invalidate channels/observers; analytics expire by TTL only
    • Pre-warmed on startup: subpaths, RF, topology, channels, hash-sizes, bulk-health
    • Result: most API responses served in 1-2ms from cache

Key Optimizations

  • Eliminated all LIKE '%pubkey%' queries: Every node-specific endpoint was doing full-table scans on the packets table via decoded_json LIKE '%pubkey%'. Replaced with O(1) pktStore.byNode Map lookups.
  • Single-pass computations: Channels, analytics, and subpaths computed in one loop instead of multiple SQL queries.
  • Client-side WebSocket prepend: New packets appended to the table without re-fetching the API.
  • RF response compression: Server-side histograms + scatter downsampling (1MB → 15KB).
  • Configurable everything: All TTLs, packet store limits, and thresholds in config.json.

What Didn't Work

  • Background refresh (setInterval): Attempted to re-warm caches at 80% TTL. Blocked the event loop — Node.js is single-threaded. Response times went from 3ms to 1,200ms. Reverted immediately.
  • Worker threads: structuredClone overhead of 416ms for 28K packets negated the compute savings. Only viable at 10× data growth or with SharedArrayBuffer (zero-copy).

Running the Benchmark

# Stop the production server first
supervisorctl stop meshcore-analyzer

# Run A/B benchmark (launches two servers: old v2.0.1 vs current)
./benchmark-ab.sh

# Restart production
supervisorctl start meshcore-analyzer