Run GLM‑5.1 Locally on CPU and GPU

GLM‑5.1 is a recent large language model that targets long tasks, coding, and complex automation. Many guides focus on cloud APIs, but more users want private local setups.

This guide explains how to run GLM‑5.1 style models on a single machine, with both CPU and GPU paths. It uses examples based on the GLM‑5 and GLM‑5.1 series, which share the same core architecture.

What Is GLM‑5.1

GLM‑5.1 belongs to the GLM‑5 family from Zhipu AI, built for long‑horizon agent tasks and strong coding performance. Long‑horizon tasks mean the model can work on the same job for hours while it plans, runs tools, and improves results.

GLM‑5 uses a Mixture‑of‑Experts (MoE) design with many experts, but only a few active for each token, which keeps runtime cost closer to a smaller dense model. The family supports context windows around 200k tokens, so it can handle large code bases, long logs, and big document sets in one session.

GLM‑5.1 shares the same glm_moe_dsa MoE architecture as GLM‑5, but uses updated weights. In evaluations, GLM‑5 already scores strongly on math, reasoning, tool use, and coding suites such as SWE‑bench and Terminal‑Bench.

Key Features

• Long context window (around 200k tokens)
  This allows large code repositories, multi‑file projects, and long documents in a single prompt.
• Mixture‑of‑Experts (MoE) architecture
  GLM‑5 and GLM‑5.1 use many experts but activate only a small group for each token, which reduces active parameters and compute cost compared with a dense model of the same total size.
• Asynchronous and tool‑aware reasoning
  The series supports tool calling and long chains of actions, which helps in coding agents and system‑level automation tasks.
• High‑end benchmark performance
  GLM‑5 reaches strong scores on exams such as AIME 2026, GPQA‑Diamond, and SWE‑bench Verified, close to or above many other frontier models.
• 200k context on local stacks
  vLLM recipes and FP8 deployments expose near‑full context on multi‑GPU systems, which is important for long‑running agents.
• Quantized GGUF builds for local use
  Unsloth provides 2‑bit and 1‑bit GGUF quantizations for GLM‑5, which reduce disk size from about 1.65TB to as low as 176GB, and make local CPU and single‑GPU use realistic.

How to Install or Set Up

This section focuses on a practical path for local users: quantized GGUF models on llama.cpp for CPU and modest GPUs, plus notes on vLLM for high‑end GPU servers.

Step 1: Check Hardware and Choose a Path

1. Confirm your target: private experimentation on a workstation or high‑throughput use on a GPU server.
2. For CPU or single prosumer GPU, choose Unsloth GLM‑5 GGUF quantizations such as UD‑IQ2_XXS or related variants.
3. For multi‑GPU data center setups, consider FP8 GLM‑5 or GLM‑5.1 through vLLM, which expects around eight high‑memory GPUs for full context.

Step 2: Install llama.cpp for CPU and GPU

Llama.cpp is a C++ inference engine for GGUF models, including GLM‑5 quantizations. It can run on CPU only, or offload layers to CUDA or Metal GPUs.

1. Install build tools such as cmake, a compiler, and curl on your Linux or macOS system.
2. Clone the official llama.cpp repository from GitHub.
3. Configure the build. Use -DGGML_CUDA=ON if you have an NVIDIA GPU, or -DGGML_CUDA=OFF for CPU‑only or Metal on macOS.
4. Build the binaries, which include llama-cli for one‑shot prompts and llama-server for an OpenAI‑style HTTP API.

Step 3: Download GLM‑5 / GLM‑5.1 Style GGUF

Unsloth publishes GLM‑5 GGUF files that you can treat as weight‑compatible with GLM‑5.1 style usage for many local tasks. At the time of writing, GLM‑5 quantized files are documented, and GLM‑5.1 quantizations follow the same pattern.

1. Install the huggingface_hub tool with Python.
2. Use hf download or snapshot_download to fetch unsloth/GLM-5-GGUF and the desired quantization, for example UD‑IQ2_XXS (dynamic 2‑bit) or 1‑bit variants.
3. Ensure you have enough disk and memory. The 2‑bit dynamic file uses about 241GB of disk, down from 1.65TB for the full model.
4. Place the GGUF files in a folder you control, for example unsloth/GLM-5-GGUF.

Step 4: Prepare CPU‑Only or Hybrid CPU+GPU Use

Even quantized GLM‑5 class models are large, so you must plan memory use.

• For CPU‑only:
  Aim for around 180–256GB of system RAM for 1–2 bit quantizations. Unsloth notes that 1‑bit variants fit in about 180GB RAM, while 2‑bit variants work with a 24GB GPU plus 256GB RAM using MoE offloading.
• For CPU+GPU hybrid:
  Use llama.cpp flags such as --n-gpu-layers and optional -ot patterns (for other GLM models) to keep MoE or FFN layers on CPU while dense layers run on GPU. This pattern from GLM‑4.7 guides shows how offloading MoE layers to CPU can let a 40GB GPU handle the rest.

Step 5: Optional High‑End vLLM Setup

For users with access to multiple H200‑ or B200‑class GPUs, vLLM recipes are available for GLM‑5 and GLM‑5.1 FP8 deployments.

1. Install vLLM nightly with CUDA support and a recent transformers build.
2. Serve an FP8 GLM‑5 model such as unsloth/GLM-5-FP8 with vllm serve, using tensor parallel size 8, FP8 KV cache, and a maximum model length around 200k tokens.
3. Expect VRAM needs of about 860GB or more across GPUs, for example 8× H200 cards.
4. Use the OpenAI API compatible endpoint that vLLM exposes for inference from Python or other clients.

How to Run or Use It

This section shows how to work with GLM‑5.1 style GGUF on llama.cpp, then how to expose it as a local API and call it from Python.

Running GLM‑5 Style GGUF on CPU

1. Set LLAMA_CACHE to the folder with your GGUF files.
2. Run llama-cli with a quantized model path and a moderate context size, for example 16k tokens.
3. Pass generation parameters such as temperature, top‑p, and minimum probability.

An example command for a CPU‑focused run with 2‑bit quantization looks like this (paths are illustrative):

bash./llama-cli \
--model unsloth/GLM-5-GGUF/UD-IQ2_XXS/GLM-5-UD-IQ2_XXS-00001-of-00006.gguf \
--threads 32 \
--ctx-size 16384 \
--temp 0.7 \
--top-p 1.0 \
--min-p 0.01

This follows Unsloth’s guidance for GLM‑5 default settings and context length, but you can adjust thread count and context window to match your CPU.

Running with GPU Offload

To speed up generation, enable GPU offload.

• Add --gpu-layers or --n-gpu-layers to move a number of transformer layers onto the GPU.
• Keep part of the model on CPU when VRAM is limited, especially MoE layers, which can sit on CPU with patterns similar to GLM‑4.6 offload settings.

On systems with one 24GB GPU and about 256GB RAM, Unsloth reports that GLM‑5 2‑bit quant runs with MoE offloading and remains usable for long context reasoning.

Serving GLM‑5.1 Style Models as an API

For real projects, an HTTP API is often more convenient.

1. Start llama-server with your GGUF model, a context length, and generation parameters.
2. Give the model an alias, for example "unsloth/GLM-5", and choose a port such as 8001.
3. From Python, use the OpenAI client with a base URL pointing to http://127.0.0.1:8001/v1 and a dummy API key.

This pattern mirrors the GLM‑4.6 and GLM‑5 code examples in Unsloth docs and works well for GLM‑5.1 style local use.

Example: Local Coding Assistant

Once your server is running, you can build a local assistant for coding.

• Create a system prompt that sets behavior, for example “You are a careful code assistant. Explain each change briefly.”
• Send user messages that include code snippets and questions.
• Use GLM‑5.1’s long context to supply whole files or project sections.

Because GLM‑5 benchmarks show strong results on SWE‑bench Verified and Terminal‑Bench, this family suits code understanding and multi‑step refactoring tasks.

Benchmark Results

Public data today focuses on GLM‑5, which shares architecture and scale with GLM‑5.1, so these benchmarks give a clear picture of expected capability.

GLM‑5 Benchmarks vs Other Models

Scores below come from Unsloth’s GLM‑5 documentation, which aggregates results from Z.ai benchmark reports.

These results show that GLM‑5 stands near the top tier for coding, browsing, and agent benchmarks, though specific leaders vary by task. GLM‑5.1 is presented by Z.ai as a refinement over GLM‑5 with stronger long‑horizon coding performance.

Testing Details

Since the model is large, most public evaluations use cloud or multi‑GPU setups. However, local users can still understand what was measured and how this relates to home or lab environments.

What Official Tests Measure

• Long‑horizon coding and system tasks
  Z.ai benchmarks GLM‑5.1 on long engineering pipelines, such as building a full Linux desktop or optimizing machine learning kernels over thousands of tool calls.
• Standard public leaderboards
  GLM‑5 scores cover exams like HLE, AIME 2026, and GPQA‑Diamond, along with SWE‑bench variations for real code changes.
• Agent and tool use
  Benchmarks such as Terminal‑Bench 2.0, BrowseComp, τ²‑Bench, and Tool‑Decathlon measure the ability to plan, call tools, and manage browsing or terminal sessions.

How Tests Are Run

Z.ai and partners run these suites on cloud instances with access to many GPUs and full‑precision or mixed‑precision models.

For example, FP8 GLM‑5 deployments in vLLM expect around 860GB of GPU memory, often across eight H200‑class GPUs.

Long‑horizon tests run for up to eight hours, where the model can plan, run code, evaluate results, and refine its approach without human prompts.

What This Means for Local Users

Local CPU and single‑GPU runs use quantized models, so token throughput and maximum context are lower than cloud FP8 deployments.

However, the same training and architecture still drive reasoning quality, especially for code and step‑by‑step tasks.

With enough RAM and a 2‑bit quantization, a workstation can host GLM‑5 class models for private software experiments, research, or internal tools.

Comparison Table

This table compares GLM‑5.1 with three other models that appear beside it in published benchmarks or related documentation.

GLM‑5.1 sits at the top of this stack, with GLM‑5 GGUF as today’s practical base for local experiments. GLM‑4.6 vs Qwen3-Max, GLM‑4.6V‑Flash and GLM-4.7 remain attractive.

Pricing Table

Running GLM‑5.1 style models involves both local costs and optional cloud options. Exact token prices change over time, but current documentation shows the main patterns.

For many users, the local GGUF path has zero marginal token cost but requires careful planning for RAM and disk. Cloud APIs, in contrast, reduce setup work and scale more easily but charge per token and may involve data‑handling rules that differ from local privacy requirements.

Unique Selling Points (USP)

GLM‑5.1 stands out for its focus on long‑horizon agent tasks combined with open deployment paths.

It targets long context, strong coding, and complex system workflows, while also offering MoE‑based efficiency and quantized variants that make on‑prem or home lab use realistic.

Few models today combine eight‑hour autonomous task runs, 200k context, and day‑zero GGUF quantization plans in the same stack.

Pros and Cons

Pros

• Long context window supports large code bases and document sets in one session.
• Strong benchmark results on coding and agent tasks compared with earlier GLM models like GLM-Image.
• MoE design reduces active parameters and compute at inference time.
• Quantized GGUF builds enable private local runs on high‑RAM systems.
• Works with llama.cpp, vLLM, and NeMo AutoModel stacks, which gives multiple deployment choices.

Cons

• Even 2‑bit quantized models need hundreds of gigabytes of combined RAM and VRAM.
• Full FP8 deployments require clusters with many high‑end GPUs, which limits access.
• Setup and tuning are more complex than small consumer‑grade LLMs.
• Local support for GLM‑5.1 weights often lags the cloud release, so early users rely on GLM‑5 quantizations.

Quick Comparison Chart

The table below gives a compact view of GLM‑5.1 compared with earlier GLM releases and a popular alternative.

For users who want maximum long‑running autonomy and can support the hardware, GLM‑5.1 is the main target. For smaller labs, GLM‑5 GGUF and GLM‑4.6 GGUF remain more realistic starting points.

Demo or Real‑World Example

This section walks through a realistic coding‑assistant workflow using GLM‑5 GGUF as a stand‑in for GLM‑5.1 on a workstation.

Scenario

You have a monorepo for a web service with thousands of lines of code. You want a local assistant that can read whole files, answer questions, and suggest changes, without sending code to external servers.

Step 1: Prepare the Model Server

1. Start llama-server with your GLM‑5 GGUF model and a context size of 16k or higher.
2. Use an alias such as "unsloth/GLM-5" and set port 8001.
3. Confirm the server responds to simple health prompts.

Step 2: Build a Simple Client Script

1. In Python, configure the OpenAI client with base URL http://127.0.0.1:8001/v1 and a dummy key.
2. Write a function that reads a source file and sends it with a prompt asking for a summary and risk review.
3. Include a short system message that asks the model to stay accurate, mention uncertainties, and avoid direct edits without explanation.

Step 3: Use Long Context for Project‑Level Tasks

With GLM‑5’s large context, you can send:

• A main file and several helper modules in one request.
• A description of the bug or business goal.
• A request for a list of refactoring steps and a small patch suggestion.

Because GLM‑5’s benchmarks show strong results on SWE‑bench Verified and related coding tasks, it can propose realistic edits. You still review each change, but the model reduces the time to understand and restructure complex code.

Step 4: Extend to Agents

Later, you can wrap this setup in an agent loop. The agent can:

• Call the model to plan steps.
• Apply edits with a script.
• Run tests and feed logs back into the model.
• Continue until all tests pass or a time limit is reached.

This mirrors the long‑horizon workflows that GLM‑5.1 targets in Z.ai’s internal evaluations, but on a smaller local scale.

Conclusion

GLM‑5.1 belongs to a new wave of long‑horizon models that blend strong coding ability, long context, and agent‑ready design. Running it in full form still needs large GPU clusters, but quantized GLM‑5 GGUF builds make similar behavior possible on high‑RAM workstations.

Tools like llama.cpp, vLLM, and NeMo AutoModel give flexible paths for CPU‑only, hybrid, and multi‑GPU setups.

FAQ

1. Can I run GLM‑5.1 on a normal home PC?

Most home PCs do not have enough RAM for GLM‑5 class models. A practical local setup today needs at least 180–256GB RAM plus a mid‑range or better GPU for 2‑bit GGUF.

2. Is GLM‑5.1 fully open source?

GLM‑5 and GLM‑5.1 are released as open or source‑available models with specific license terms. Always read the official license from Z.ai or your provider before commercial use.

3. How does GLM‑5.1 compare with GPT‑style frontier models?

Benchmarks show GLM‑5 close to or slightly behind some GPT‑ and Gemini‑class models on certain tasks, but ahead on others like some tool and agent suites. GLM‑5.1 improves long‑horizon engineering performance while keeping strong coding and reasoning.

4. What is the best way to start if I only have 64GB RAM?

With 64GB RAM, GLM‑5 class models are not practical. Start instead with smaller GLM‑4.6V‑Flash or other 7–9B models in GGUF, then move to GLM‑5 GGUF when you upgrade hardware.

5. Can I fine‑tune GLM‑5.1 locally?

Fine‑tuning full GLM‑5 or GLM‑5.1 requires multi‑GPU setups and frameworks like NeMo AutoModel, which scale across many H100‑ or H200‑class GPUs. For most users, LoRA‑style adapters or prompt engineering on quantized GGUF models are more practical paths.