The work in artificial intelligence (AI) continues to be informed by scaling laws, which define the relationship between performance and the size of the dataset, the number of parameters, and the resources allocated to computation. Scaling within the training phase is relatively straightforward. In general, performance improves when information is abundant, models are sufficiently sized, and when computing resources are sufficiently large.
However, the challenge of execution at scale comes into play when it is time to perform inference. AI inference involves generating predictions, classifications, or responses. In any given system, latency, throughput, and compute cost dictate whether it is feasible for real-world use. Inference time scaling laws are crucial for accurate predictions of observables in systems with varying workloads, aiding researchers, engineers, and system designers.
This article analyzes the nascent field of inference scaling for IT professionals at all levels. Firstly, it considers the systems view, which illustrates the impact of scaling laws on server architecture, interconnect topology, and resource distribution. This will help to clarify the divide between the infrastructure and scaling perspectives. Once that is understood, the potential implications of research on artificial intelligence deployment come more sharply into focus.
Find out about the limits of inference, the efficiencies involved, and the trade-offs that are generally made in real-world scenarios.
Emerging from large experiments focused on language models and vision systems, scaling laws were first noticed in the relationships between model size, dataset size, and the computational expenditure. For instance, a model with a larger set of parameters will improve accuracy so long as the data and compute resources also increase. It is this kind of incremental improvement that justifies the ever-increasing cost of foundation models.
Training scaling laws focus on the improvement of performance in the learning process. Inference laws operate on runtime metrics, which include cost, latency, and the accuracy of executing a trained model. Although they are less studied, these laws are critical as they define the efficiency of model operations in production systems that service millions of users.
There are three relevant scaling categories. Pre-training scaling focuses on accuracy. It deals with the model expansion that delivers performance improvements. Post-training scaling covers performance enhancements and includes techniques including fine-tuning, transfer learning, and chaining of reasoning modules. Test-time scaling explores the emerging paradigm where additional inference compute, long thinking, results in better answers without the need for retraining.
Research now has a set of boundaries defined by the scaling laws which connect research choices with the realities of deployment.
Inference time is impacted by a range of interconnected factors, foremost among them model architecture, which relates directly to the number of parameters in a model as well as its layers. Increasing both parameters and deepening layers will demand more operations at each prediction. In natural language processing, systems that utilize transformer models are popular. However, these models have a quadratic attention mechanism, which is known to scale poorly with sequence length.
Precision factors are equally as important. Using FP32 (32-bit floating point) boosts the accuracy of the model; however, accuracy comes at the cost of FP32’s memory and compute cycles. Lower precision formats, such as FP16 (16-bit floating point), BF16 (16-bit brain floating point), or INT8 (8-bit integer), make inference more efficient in terms of time, ease memory bandwidth pressure, and reduce the number of compute cycles needed. These precision trade-offs should be accounted for when scaling laws are derived, as inference and computation will demand differing resources.
Throughput is improved by larger batch sizes; however, the systems need to balance responsiveness expected and the precision required. Inference services are likely to encounter this trade-off, as larger batch sizes can decrease cost to provide resources to complete tasks.
Note, too, that I/O and memory bandwidth are likely to lag due to lower performance. While a graphics processing unit (GPU) or accelerator may provide high theoretical floating-point operations per second (FLOPs), performance depends on data transfer through the memory hierarchy. Maintaining efficiency depends on data transfer through the memory hierarchy, which is greatly improved by High Bandwidth Memory (HBM), cache optimization, and fast interconnects such as NVLink or PCIe Gen5.
An inference law that is presumed to operate with unrestricted bandwidth, or where I/O is negligible, offers little utility. Infrastructure planners require some laws which consider limits based on deployment.
In the case of large language models (LLMs), inference costs increase in proportion to the model size. In token-by-token generation, however, latency scales with the number of parameters for each layer. It also grows in accordance with the length of the sequence being processed, an important consideration. Bear in mind, too, that although such a relationship is nearly linear in most cases, it will invariably improve when optimization techniques are deployed. A good example is caching, which prevents repeated computation for long sequences.
Throughput scaling is often sub-linear. Increased batch size does not always result in a proportionate increase in throughput in enterprise AI deployments. This is particularly true with diffusion models, where the generation of an image requires multiple sampling steps which stress memory and compute resources.
For example, OpenAI’s model o1 spends additional compute resources during reasoning. Accuracy improves significantly during additional pass processing, simulating multiple chains of thought, or lengthened generation. This is a deviation from the traditional benchmark of efficiency, where the inference is set in stone; a model is able to provide better returns if additional computation is allocated during reasoning rather than during training.
These considerations indicate that when constructing reasoning scaling laws, the fixed parameter of model size should include a parameter for the model’s strategies in runtime reasoning.
Providing a scaling law greatly assists in the planning of infrastructure as it sets a baseline. The order of operations matters. Attention-based computer vision reasoning often needs to meet a set number of operations in a given time, while natural language reasoning deals with an order of magnitude larger.
Moving a notch deeper, inference at the node level is a result of the combination of the inference accelerator, the balance between the node’s memory bandwidth, and its thermal design. While high-end GPUs with tensor cores excel at parallel processing for FP16 or INT8 workloads, some systems with lower-grade GPUs, or other systems with custom ASICs, outperform in low and controlled workloads. The same applies to CPU offloads used for tasks unrelated to the core AI systems.
Network design and interconnects become even more critical when clusters are involved. Helpfully, InfiniBand provides high-bandwidth connectivity between nodes, while NVLink enables fast GPU-to-GPU communication. High-speed Ethernet is sufficient for flexible scaling across racks. To satisfy user demand for inference workloads, orchestration, containerization, and dynamic resource allocation become critical as horizontal scaling is often required.
Two practical limits, cooling and power density, cannot be ignored. As inference loads scale, the energy cost associated with deployment approaches or surpasses the cost of training. Efficient cooling systems, such as direct-to-chip liquid cooling, improve denser rack configurations and lower operating costs.
Organizations are now reworking the logic of model training and focusing on servicing models cost-effectively for millions of users instead of just training the largest model possible.
Traditional scaling laws placed the most importance on pre-training. A model trained by engineers was given fixed costs of inference based only on the number of parameters and the hardware used. The new reality is that there is a dynamic picture.
Post-training scaling offers further task-specific adaptation of a base model. Domain-specific data, when used for fine-tuning, improves inference efficiency for a given task. In a similar fashion, modular methods, for example, retrieval-augmented generation, compose specialized parts together, thus distributing inference among subsystems. The scaling laws in this case explain how incremental training improves efficiency in greater inference.
Even more novel is test-time scaling. This innovation seeks to augment inference costs, not reduce them. Performance improves when a model is allotted more computing cycles during inference, whether through deeper reasoning passes, wider beam searches, or multiple self-consistency checks. This enables the cost curve to be shifted, allowing for greater accuracy alongside reduced pre-training returns.
For infrastructure providers, these trends translate to the other mode of inference requiring additional compute. Simple inference requests necessitate ultra-low latency, while “thinking” demands compute cycles for deeper reasoning. This need is further driving a change in system architecture.
From a company’s point of view, inference is usually the largest portion of an AI system’s cost. Training a model can cost billions of dollars, while the model itself may serve billions of requests over its lifetime.
Inference scaling laws support organizational cost forecasting. For example, if energy consumption is super-linear with scaling, serving larger model sizes becomes economically unfeasible. Query latency may be improved with batch processing, but this technique would make real-time latency unacceptable.
Allocating more computing power per inference during lower-tier queries improves accuracy but also raises the request cost. Organizations have to make a decision on how the cost increases and the quality of responses it provides the company.
The acquisition cost of an organization’s AI hardware is no longer the only concern. Infrastructure footprint and operational efficiency are additional factors to consider. With regard to cooling, powering, and operational efficiency, the total ownership cost can be greatly improved.
Let’s consider some example cases of AI inference time scaling laws in real-world scenarios.
A large search engine that uses a billion-parameter model for real-time ranking. Latency is a critical issue here, and must not exceed a few milliseconds. This sharpened focus constrains engineers to using INT8 inference with specific batch size tuning.
A chatbot powered by generative AI that supports millions of users simultaneously. In this case, maximum throughput is the bot’s most critical performance metric. While users may receive responses with a slight delay, the system utilizes batch inference and comprehensive cluster-wide orchestration for optimal resource efficiency.
The last scenario is an edge installation for self-driving cars. While latency and real-time response remain critical, available computing capabilities are limited. Scaling laws illustrate the relationship between a model’s size and the ability to perform real-time inference. Engineers are forced to use AI automation designs that maintain safety margins while not exceeding the constrained hardware.
In all of the examples, constraining capacity in planning, resource allocation, and infrastructure design is guided by inference scaling laws.
Research into scaling laws is ongoing, if inconsistent. One current area of study lies in integrating energy costs directly into the laws. Metrics such as joules per inference may become as important as floating point operations per second (FLOPs).
Models of new architectures, such as mixture-of-experts models, can change the scaling profile by activating a set of parameters during inference. While the computing expense of a model is reduced, accuracy is retained on large models. Evolving scaling laws to address these conditional computations is essential.
Areas such as photonic accelerators, neuromorphic chips, and custom inference ASICs offer the potential to shift scaling curves.
A forecasting model that predicts end-to-end costs and performance would allow organizations to assess efficiency before embarking on massive training runs. This model would help businesses stay within budget and run efficiently.
Community benchmarks and open datasets would help determine consistent measures across tested models and hardware. These types of benchmarks would aid in maintaining the accuracy of measurements over various systems and hardware, thus improving the outcome of the overall experiment.
There is growing confidence that scaling laws are no longer confined to training. The costs and efficiency of technology used during and after AI systems are deployed are key factors that need to be addressed and understood. The deployment of AI technology allows systems to focus on various angles such as latency, throughput, and accuracy.
Changes within the infrastructure are necessary to support reasoning workloads paired with ultra-low latency.
The predictions made based on post-training and test-time scaling broaden the scope, showing that inference is not as static or fixed as originally believed.
Following the scaling laws approach, companies will be able to learn firsthand the process of model development, hardware deployment, and data center modernization. AI systems will naturally evolve while staying cost-efficient, sustainable, and responsive to various needs and expectations.