Profilers show what ran, not what to change
A timeline of kernels and API calls still leaves an engineer to connect it to the scheduler, KV cache and batching, and to work out which fix is worth making.
Horus is an AI performance engineer for LLM inference. It traces SGLang and vLLM deployments end to end, finds where performance is lost, and uses agents to fix it, delivering benchmark-verified code you keep.
Inference optimization
One decode iteration, zoomed in on a single block to show why it finishes sooner.
Same workload · same horizontal scale
N / S / Q = normalize / scale / quantize. A / B = chunks. D = dispatch; R = return. G = gate. P = post.
Fewer boundaries
Merge compatible work; reduce launches and intermediate memory traffic.
Shorter device execution
The same operation, checked against a reference, in less time on the device.
Less exposed communication
Send B while computing A; return A while computing B. Dependencies are preserved.
Hold model, hardware, batch, context and speculation policy constant when comparing measured traces.
Illustration, not measured data. Lanes show logical work, and communication may execute inside a fused GPU kernel. No measured latency, speedup or claim about default SGLang behavior is represented.
The gap
A timeline of kernels and API calls still leaves an engineer to connect it to the scheduler, KV cache and batching, and to work out which fix is worth making.
A configuration change rewrites almost every answer, even when quality is unchanged. Without a way to prove quality held, teams stay on the safe default.
The engine sizes its KV cache from free GPU memory at start-up, and that moves between runs. Without controls at the same cache size, luck reads as progress.
Defaults can be wrong in ways only the source code reveals, and the best settings change with every model and every hardware configuration.
The floorplan
Attention, matrix-multiply and MoE kernels, plus GPU-to-GPU collectives. Agents write and tune replacements at the exact shapes your workload uses.
Draft depth, draft precision and acceptance, priced against the cost of each decode step.
How much cache the engine gets, and what owns the rest of each GPU’s memory.
Running batch, waiting queue and the prefill work that interrupts decode.
How one model’s work is split across the GPUs in a node.
CPU work and pauses that leave GPUs waiting.
Overhead from compiling the model and capturing its GPU graphs.
One profiling run of your real workload, on the engine you already use, from engine flags down to individual GPU kernels.
Find where performance is lost and explain why, whether that is a flag, the parallel layout, memory, communication or a kernel.
Specialised agents each take one part of the system and propose changes: configuration, engine patches and rewritten kernels.
Every proposal runs on a clean server beside control runs. Only changes that are faster and pass accuracy checks are kept.
You keep the code and the configurations. Horus can run fully on-premises, so your data never has to leave.
Who it’s for
Horus is built to put a measured number on every one of them.
The first engagement
A scoped pilot covers one model, one supported deployment and one representative workload, with the baseline, quality checks and experiment budget agreed up front.
Talk to us
horus.io.gpu@gmail.com