Groq Performance Tuning

Overview

Maximize Groq's LPU inference speed advantage. Groq already delivers extreme throughput (280-560 tok/s) and low latency (<200ms TTFT), but client-side optimization -- model selection, prompt size, streaming, caching, and parallelism -- determines whether your application fully exploits that speed.

This skill walks through six tuning levers at a high level; the complete, copy-pasteable code for each lives in references/implementation.md, and end-to-end worked scenarios live in references/examples.md.

Prerequisites

• Groq API key — set GROQAPIKEY in the environment. The groq-sdk client (new Groq()) reads it automatically; never hardcode the key.
• Node.js 18+ with the groq-sdk package installed (npm install groq-sdk).
• Optional packages for the caching and parallelism steps: lru-cache and p-queue (npm install lru-cache p-queue).
• A baseline latency measurement of your current integration so you can confirm the tuning actually helps.

Groq Speed Benchmarks

TTFT = Time to First Token. Actual values depend on prompt size and server load.

Instructions

Apply these six levers in order. Each is a small, independent change — start with the ones that match your bottleneck (model choice and caching give the biggest wins on most workloads). The full code for every step is in references/implementation.md.

1. Choose the right model for speed. Map each call site to a speed tier: llama-3.1-8b-instant for latency-critical paths, llama-3.3-70b-versatile for quality-sensitive paths, llama-3.3-70b-specdec for 70b quality at higher throughput. Set temperature: 0 so responses are deterministic (and cacheable).
2. Minimize token count. Trim verbose system prompts to their essence and set max_tokens to the expected output size, not a safe-looking ceiling. Fewer tokens means faster responses and less TPM-quota pressure.
3. Stream for perceived performance. For any output the user watches arrive, stream chunks and surface live TTFT / tokens-per-second metrics. Streaming hides TTFT even when total wall-clock is unchanged.
4. Cache deterministic responses. Hash {messages, model} and serve repeat temperature: 0 requests from an LRU cache with a short TTL — turning a repeated call into a ~0ms hit.
5. Parallelize under a rate-limit-aware queue. Fan out bulk work with p-queue, capping concurrency and per-minute volume so you saturate throughput without tripping 429s.
6. Benchmark before you commit. Measure the candidate models against your real prompt shape and pick the fastest that clears your quality bar.

The essential skeleton — a tiered client every other step builds on:

import Groq from "groq-sdk";

const groq = new Groq();  // reads GROQ_API_KEY from the environment

const SPEED_MAP = {
  instant: "llama-3.1-8b-instant",      // <100ms TTFT — latency-critical
  balanced: "llama-3.3-70b-versatile",  // <200ms TTFT — quality-sensitive
  fast70b: "llama-3.3-70b-specdec",     // 70b quality, faster throughput
} as const;

async function tieredCompletion(prompt: string, tier: keyof typeof SPEED_MAP = "instant") {
  return groq.chat.completions.create({
    model: SPEED_MAP[tier],
    messages: [{ role: "user", content: prompt }],
    temperature: 0,   // deterministic = cacheable
    max_tokens: 256,  // request only what you need
  });
}

See references/implementation.md for the streaming, caching, parallel-queue, and benchmarking functions in full.

Output

Applying these levers to a Groq integration produces:

• A tiered model map (SPEED_MAP) so each call site uses the fastest model that meets its quality bar.
• A streaming helper that returns { content, ttftMs, totalMs, tokPerSec } for live latency instrumentation.
• A deterministic prompt cache (LRU + SHA-256 key) that collapses repeated requests to ~0ms.
• A rate-limit-aware parallel executor that maximizes throughput without hitting 429s.
• A benchmark report printing average latency and tokens/sec per model, e.g.:

llama-3.1-8b-instant     |  61ms avg | 548 tok/s avg
llama-3.3-70b-versatile  | 148ms avg | 279 tok/s avg
llama-3.3-70b-specdec    | 103ms avg | 401 tok/s avg

Performance Decision Matrix

Examples

Common scenarios mapped to the levers above. Full code for each is in references/examples.md.

• Latency-critical classification — 8b-instant + one-word prompt + max_tokens: 5 + cache. First call ~50ms TTFT; identical repeats return from cache at ~0ms.
• Interactive chat — 70b-versatile streamed with streamWithMetrics, printing tokens as they arrive plus a [TTFT | tok/s] footer.
• Bulk processing (500 records) — parallelCompletions wraps each call in a rate-limit-aware p-queue and reuses the cache for duplicate rows.
• Empirical model choice — run benchmarkModels against your real prompt, then hardcode the fastest tier that clears your quality bar.

// Latency-critical classification, cached
const label = await cachedCompletion(
  [
    { role: "system", content: "Classify as positive/negative/neutral. One word only." },
    { role: "user", content: "This product exceeded every expectation." },
  ],
  "llama-3.1-8b-instant"
);
// => "positive"

See references/examples.md for the streaming, bulk, and benchmarking walkthroughs.

Error Handling

Resources

• Full implementation walkthrough — copy-pasteable code for all six steps.
• Worked examples — end-to-end scenarios mapped to the tuning levers.
• Groq Models & Speed
• Groq Rate Limits
• lru-cache on npm
• For cost optimization, see the groq-cost-tuning skill.