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06 Numbers and Powers

LLM Hosting Options: Match APIs, Endpoints, and GPUs

Card No. 06·57874 · Updated · Standard formula, shown below

LLM hosting options match an application’s API requirements, traffic pattern, and latency goals to a suitable serving model and GPU setup. The practical choice is usually between a hosted model API, a managed dedicated endpoint, or self-hosting on rented or owned GPUs; each offers a different balance of convenience, control, cost, and operational work.

What LLM hosting means

Hosting is the system that loads a language model, accepts prompts, runs inference, and returns generated tokens. An API is the interface an application calls; an endpoint is the reachable service address and its deployment configuration; a GPU is hardware that can accelerate model computation. These terms are related but not interchangeable: an API can route to many machines, and a GPU can serve multiple endpoints or models.

Most applications send a request containing messages or a prompt, settings such as a token limit, and sometimes structured output or tool instructions. The service returns generated text and often usage or timing information. Compatibility depends on the request and response format, authentication, streaming support, context limits, and provider-specific features—not simply on whether both systems are described as “LLM APIs.”

Three common hosting models

  • Shared hosted API: A provider operates the model and infrastructure. This is often the quickest way to prototype or serve variable demand. You generally have less control over hardware, model versions, scheduling, and low-level inference settings.
  • Managed dedicated endpoint: A hosting service deploys a selected model on reserved or separately configured capacity and exposes an API. It can provide more predictable configuration and isolation than a shared service, while leaving much of the infrastructure management to the provider.
  • Self-hosted inference: Your team deploys and operates the serving software on rented cloud GPUs or owned hardware. This can offer control over model selection, batching, networking, and data handling, but requires expertise in deployment, monitoring, scaling, and updates.

Product labels vary. Check what is actually dedicated, what is shared, where requests are processed, and whether the provider manages scaling and model updates.

Match the workload to the endpoint

Start with the application’s behavior rather than choosing a GPU first. A low-volume internal assistant may work well with a shared API. A public service with sustained traffic may need a provisioned endpoint to improve predictability. A batch job that can wait may prioritize throughput and low cost per processed token over interactive response time.

  • Interactive chat: Consider time to first token, streaming, tail latency, and burst handling. Streaming can make a response feel faster, but does not necessarily reduce the total time to generate it.
  • Batch summarization or extraction: Look for efficient batching, throughput, and the ability to queue work. If jobs are not time-sensitive, off-peak capacity may be useful where the service supports it.
  • Tool-using or structured applications: Verify support for the required tool-call format, JSON or schema-constrained output, and any relevant limits. Similar feature names do not guarantee identical behavior across APIs.
  • High or unpredictable traffic: Check autoscaling behavior, concurrency limits, cold starts, rate limits, and what happens when capacity is exhausted. A service that scales eventually may still be unsuitable for sharp bursts.

Measure representative requests. Prompt length, output length, context size, concurrency, and streaming all affect resource use and response time. A short test prompt is not a reliable forecast for a production workload.

How to choose GPU capacity

Model size is only one part of GPU sizing. The model’s weights must fit in memory, alongside the serving software and temporary memory used during inference. Input and generated tokens require additional working memory, often called a key-value cache. Longer contexts and more simultaneous requests can increase that requirement substantially.

Quantization stores model weights at lower numerical precision to reduce memory use and sometimes improve throughput. It can also affect output quality or compatibility, so validate it on representative tasks. Multiple GPUs can support larger models or higher throughput, but splitting work across devices adds complexity and does not guarantee a proportional speed increase.

Compare the actual deployment configuration: GPU model and memory, number of GPUs, model precision, context limit, concurrency, batching, and inference engine. Published throughput figures are meaningful only when their model, prompt and output lengths, batch size, and measurement method resemble your own use.

Compatibility, reliability, and security

Before switching providers or moving from an API to a self-hosted endpoint, test application compatibility. Some services provide an API compatible with a familiar format, but differences can remain in parameter names, error responses, tool calls, tokenization, and model behavior. Keep provider-specific details behind an adapter where practical, and run regression tests before changing a model or serving stack.

Reliability includes more than uptime. Review rate limits, request timeouts, retry guidance, streaming interruptions, maintenance behavior, and whether the endpoint can scale to expected concurrency. Retries should be bounded: repeating a request that already completed can waste capacity or create duplicate downstream actions.

For sensitive data, establish what the service logs, how long data is retained, who can access it, and what deployment regions and access controls are available. Do not assume that an endpoint is private or that prompts are excluded from logging because it is called an API. For self-hosting, you gain control over the environment but also take responsibility for network exposure, credentials, patching, and access policies.

Cost and operational trade-offs

Hosted APIs commonly charge according to usage, such as input and output tokens, though pricing models differ. Dedicated deployments may incur charges for provisioned time or capacity, including periods of low utilization. Self-hosting adds GPU rental or purchase, storage, networking, engineering time, and operational overhead. Hardware that is idle still has a cost if it is reserved or owned.

Estimate cost using measured traffic: requests per time period, average input and output lengths, peak concurrency, and expected availability. Include retries and evaluation traffic. Then compare the complete serving options rather than the headline unit rate. A lower token rate may not help if the deployment needs several underused GPUs; a shared service can be economical at low volume but less predictable at sustained usage.

A practical selection process

  1. Define the task, quality requirements, context length, and acceptable latency.
  2. Measure typical and peak request volume, including concurrency and output size.
  3. Shortlist models and endpoints that support the required API features and data controls.
  4. Run the same representative evaluation set against each option; compare answer quality, errors, latency, and cost.
  5. Test scaling, timeouts, limits, and recovery behavior before relying on the service in production.
  6. Reassess after traffic or model needs change; hosting choices are not permanent.

Frequently Asked Questions

What is the difference between an LLM API and an endpoint?
An API defines how software sends requests and receives responses. An endpoint is the service address and deployment that accepts those requests. One API can have several endpoints, such as separate deployments for testing and production.

Do I need a GPU to use an LLM?
No. A hosted API runs the model on the provider’s infrastructure, so your application can call it without owning a GPU. GPUs matter when you operate the inference service yourself or choose a hosting arrangement whose capacity is based on GPUs.

How much GPU memory does a model need?
There is no single amount based only on the model’s name or parameter count. Weight precision, model architecture, context length, concurrent requests, and serving overhead all matter. Check deployment-specific requirements and test the intended configuration.

Is a dedicated endpoint always faster than a shared API?
No. Dedicated capacity can make performance more predictable, but speed depends on the model, hardware, serving stack, request size, and load. Benchmark realistic requests rather than relying on the hosting label.

Can I switch from one LLM provider to another easily?
Sometimes, especially when both support similar request formats, but feature and behavior differences can break integrations. Test error handling, streaming, tool use, output constraints, and model quality before switching.

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