Together AIAnnouncement
ThunderAgent: 2x Faster Agentic Inference for Synthetic Data Generation at Scale
Summary
ThunderAgent is a program-level scheduler for high-throughput agentic inference, developed by researchers at Georgia Tech, UIUC, CMU, and Together AI. It solves KV cache thrashing, which occurs when request-level engines like vLLM and SGLang evict an agent’s KV cache during tool calls and recompute it on resume, creating a cascade of evictions. ThunderAgent tracks each workflow as a schedulable program, pausing low-priority workflows under memory pressure and routing resumed programs through a global waiting queue to the node with the most available capacity. In synthetic data generation pipelines, it achieves up to 2.5x single-node throughput and 2.4x speedup on 8 nodes with near-linear scaling, and was accepted as an ICML 2026 Spotlight paper.
Context
LLMs are increasingly used as agents that multi-turn reason and use tools, requiring large-scale synthetic data generation since natural web data lacks agentic trajectories.
Approach / What changed
A lightweight scheduling layer that abstracts each agentic workflow as a schedulable program, monitoring execution phase, KV cache footprint, and node placement. It pauses low-priority workflows under memory pressure to reduce cache contention, then resumes them through a global waiting queue onto the node with the most free capacity.
Takeaways
KV cache thrashing in agentic inference occurs because request-level schedulers evict a paused agent’s KV cache, forcing recomputation that cascades across agents under high concurrency.
ThunderAgent treats each multi-turn agent workflow as a schedulable program and pauses low-priority workflows under memory pressure to improve cache hit rates for remaining active agents.
ThunderAgent replaces static node-pinning with a global waiting queue that routes resumed workflows to the node with the most free capacity, balancing cache locality and load across the cluster.
FAQ
How does ThunderAgent avoid KV cache thrashing?
It monitors memory pressure per node and selectively pauses low-priority workflows when memory is tight, reducing the number of competing agents. When a paused workflow resumes, the global waiting queue routes it to the node with the most available capacity.
Does ThunderAgent work with existing inference engines?
Yes, it is a drop-in layer requiring only a program_id field and is OpenAI-compatible, working with engine-level optimizations like speculative decoding.
What throughput gains does ThunderAgent provide?
On a single 8xH100 node with HiCache offloading at batch size 192, ThunderAgent achieves 803 tokens/s versus 390 tokens/s for the baseline, with mean latency of 10.6s compared to 65s.
Source and freshness
- Source
- together.ai
- Published
- Added to Yomu
Summaries are generated from the original by a language model. Check the original before relying on it.
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