3.1. Problem Formulation
As summarized in
Figure 1, the proposed framework connects GPU-device reconstruction, temporal aggregation, horizon-specific forecasting, baseline comparison, and performance evaluation.
The objective of this study is to predict future GPU utilization from historical telemetry as potential input to proactive resource management decisions. The released telemetry contains observations from multiple GPU devices, and the forecasting unit is defined as one reconstructed GPU device stream identified by (
Node,gpu_index), rather than a physical compute node or a sequence formed by concatenating different devices. Let
M denote the number of retained GPU devices. For GPU device
m, the utilization sequence is
where
is the GPU utilization percentage at time step
t, and
is the length of the sequence for GPU device
m.
Each GPU device is treated as an independent univariate time series. Sliding-window samples are generated separately from each device and are pooled only at the sample level. For a given forecast horizon, one global model is trained, with parameters shared across devices; parameters are not shared across different forecast horizons. Thus, every input–target pair originates from one GPU device, and the prediction target is GPU device-level utilization.
Given a look-back length
L, the historical input available at forecast origin
t is
Let
denote the evaluated forecast horizons in units of the 1 min sampling interval. For
, the raw-scale target associated with forecast origin
t is defined as
Accordingly,
denotes the prediction made at time
t for GPU device
m and target time
.
A direct horizon-specific strategy is adopted. A separate scalar model is trained for each
h:
where
denotes the parameters of the model trained for horizon
h. Predictions from shorter horizons are not recursively used as inputs to longer-horizon models.
Let
be the number of valid training windows from GPU device
m for horizon
h, and let
be the corresponding number of pooled training samples. Using a pooled sample index
n, the horizon-specific squared-error objective on the raw scale can be written conceptually as
The pooled index is only notational; it does not imply temporal continuity between different GPU devices. In the actual optimization, both inputs and targets are represented on the normalized scale defined in
Section 3.3.
For reporting the three independently trained forecasts at a common forecast origin
t, the predictions can be collected as
This vector is a reporting convenience; it is not the output of a single multi-output network, and parameters are not shared across horizons.
3.2. Experimental Objective
The experiment is designed around two practical questions. The first is whether the model ranking changes as the forecast is moved from the next minute to a longer planning horizon. We therefore use 1 min, 10 min, and 1 h targets, which correspond roughly to immediate scheduling, rolling allocation, and short-term capacity planning. These horizons are fixed analysis points rather than values selected after inspecting test performance.
The second question is how the models behave when the utilization trace departs from local continuity. For this reason, the overall test-set comparison is supplemented with spike events, high-load intervals, and a controlled zero-masking experiment. The same chronological split, eligible targets, preprocessing rules, GPU device-level macro-averaging, and diagnostic subsets are used for persistence, rolling mean, 1D-CNN, GRU, FC-LSTM, LTC, and Transformer so that differences in preprocessing do not enter the comparison. LTC provides the continuous-time recurrent alternative in this set; the experiments are used to determine whether its adaptive state dynamics are useful for these traces, rather than assuming that they are beneficial in advance.
A 60-sample input window is used throughout the study. At the 1 min resampling interval, this corresponds to one hour of recent history. Keeping this history length fixed makes the input context comparable across the three forecasting tasks. The value is a common experimental setting, not a claim that 60 min is the universally optimal look-back length.
3.3. Dataset and Preprocessing
The experiments use the January 2022 public release of the MIT Supercloud Dataset [
11]. The release is identified by the public prefix
s3://mit-supercloud-dataset/datacenter-challenge/202201/ and is described by the MIT Datacenter Challenge as the data released as of January 2022 (
https://dcc.mit.edu/data/ (accessed on 11 August 2026). The release contents and directory structure were reverified on 11 August 2026. GPU telemetry is read from the
gpu/ directory and linked to the Slurm accounting metadata in
slurm-log.csv. No additional calendar date restriction is applied in this study: all GPU timestamps available in this release are eligible before the validity and forecasting-window filters described below. The source dataset paper reports a six-month collection window and notes that collection was ongoing [
11]. Because the public release page does not publish calendar endpoints for this six-month window, unsupported start/end dates are not introduced here. Instead, the release-specific extraction procedure records the exact minimum and maximum raw and retained timestamps from the released
timestamp field in a reproducibility manifest.
The released GPU telemetry is job-oriented rather than a set of preconstructed continuous machine-level series. The MIT collection procedure monitors every GPU assigned to a job with the NVIDIA
nvidia-smi utility at 100 ms intervals [
11]. The GPU time-series schema used in the present extraction contains the anonymized identifiers
id_job and
Node, together with
timestamp,
gpu_index, and
utilization_gpu_pct. The latter is the only telemetry variable used as a forecasting input. Other released GPU measurements, such as memory utilization, memory footprint, temperature, power draw, and PCIe information, are not used by the forecasting models.
Identifier linkage follows the relationships preserved in the public release. The dataset authors added the corresponding job identifier and node name to the GPU traces because
nvidia-smi itself is not scheduler-aware, and the same anonymized identifiers are used across the released files [
11]. We therefore join GPU telemetry to
slurm-log.csv on the anonymized
id_job. The GPU
Node value is checked against the node allocation represented by the scheduler
nodelist whenever this field is available. Within a node,
gpu_index identifies the GPU device; it is not treated as globally unique. Consequently, the forecasting-series identifier is the composite key
. Scheduler fields
id_array_job and
id_array_task, when present, are inherited from the scheduler record matched by
id_job; they are metadata and are not used as an independent second join or as the forecasting series identifier. This distinction prevents job, array task, node, and GPU device identifiers from being conflated.
The public repository reports 98,177 jobs that requested GPUs, whereas the 12,568 value used in this manuscript is a study-specific post-filtering count rather than a property of the full public dataset. To remove the ambiguity in the phrase “GPU-related tasks”, we define this quantity here as 12,568 contributing GPU jobs, i.e., distinct anonymized id_job values whose GPU observations contribute to at least one of the final retained GPU device streams. Array job and array task identifiers remain attached to the scheduler records when applicable, but they are not counted as separate forecasting devices.
For temporal reconstruction, observations belonging to the same (Node,gpu_index) key are ordered by timestamp. The raw 100 ms utilization_gpu_pct measurements are then aggregated onto a fixed 1 min grid by taking the arithmetic mean of all valid observations within each minute. If no valid observation is present in a minute, the grid point is marked as missing. Thus, 100 ms is the acquisition interval of the source GPU telemetry, whereas 1 min is the forecasting resolution used in this study; therefore corresponds directly to 1-min-, 10-min-, and 1-h-ahead forecasting.
The final subset is selected in the following fixed order. First, records with an invalid
id_job,
Node,
timestamp,
gpu_index, or
utilization_gpu_pct are removed and GPU records without a matching scheduler job are excluded. Second, the remaining records are reconstructed into (
Node,gpu_index)-level streams and aggregated to the 1 min grid. Third, each stream is split chronologically into 70%/15%/15% training, validation, and test subsets, after which the split-local causal gap rules below are applied.
Figure 2 provides a schematic overview of this chronological data partition and the associated leakage prevention protocol. The 70%/15%/15% boundaries are determined separately from the available chronology of each retained GPU device stream; no universal absolute timestamp is shared across all devices. For a resampled stream of length
, define
The training subset contains indices
, validation contains
, and test contains
. Because
and the retained timestamp range can differ by device, the corresponding calendar-time split boundaries can also differ. All imputation, normalization eligibility checks, and window construction are then restricted to the resulting split-local data. Finally, a GPU device is retained only when it yields at least one eligible input–target window in
each of the training, validation, and test subsets for
all three horizons
. A validation or test target is eligible only when its target timestamp was originally observed before imputation. Applying this pipeline gives the 128 GPU device time series and 12,568 contributing GPU jobs used in the experiments. The value 128 therefore refers to retained GPU device streams, not to 128 physical compute nodes.
The raw-to-analysis extraction and audit procedure is implemented with a release-specific reproducibility script. The procedure records the release prefix, input directories/files, raw fields, join keys, minimum and maximum raw and retained timestamps, row counts after each filtering stage, number of contributing id_job values, and number of retained streams in an audit manifest. This keeps the release-specific time span and selection counts data-derived rather than manually inferred from file names or publication dates.
After temporal aggregation, each retained GPU device produces an independent univariate utilization sequence,
where
denotes the GPU utilization percentage of GPU device
m at time step
t,
is the length of its 1 min sequence, and
is the number of retained GPU device streams. Streams from different devices are neither concatenated nor averaged. Sliding-window samples are generated separately for each device and are pooled only at the sample level for global model training.
The main characteristics of the processed dataset are summarized in
Table 1.
The 8.7% natural missing ratio is calculated after 1 min aggregation and before imputation. Each GPU device sequence is then divided chronologically into training, validation, and test subsets using proportions of 70%, 15%, and 15%, respectively. Missing-value processing is performed independently inside each subset, and no filling or interpolation operation is allowed to cross a split boundary. Within a subset, forward filling is applied to gaps shorter than 10 min. For gaps from 10 to 30 min, linear interpolation is permitted only for a forecasting sample whose forecast origin occurs at or after the right-hand valid endpoint used by the interpolation. If constructing a sample would require an interpolated input that depends on an observation later than the sample’s forecast origin, the sample is discarded rather than using the future observation. Segments containing gaps longer than 30 min are also excluded from sliding-window construction. This sample-wise causality constraint prevents both cross-split leakage and within-split look-ahead leakage.
For validation and test evaluation, the target timestamp must correspond to an originally observed valid GPU utilization record before imputation. A candidate sample whose target value is missing in the resampled data before imputation is excluded from metric computation. Imputation is therefore used only to recover eligible historical input values under the causal rule above and is never used to manufacture validation or test ground-truth targets.
Artificial input corruption is introduced only in the robustness evaluation by randomly replacing originally valid normalized historical inputs with zero; the forecasting targets are left unchanged. This zero-masking protocol is therefore distinct from the naturally missing records handled during preprocessing and should not be interpreted as a realistic missing-value token.
Random splitting is avoided because it would disrupt the temporal order of each utilization sequence and could produce overly optimistic forecasting results. For the
m-th GPU device, the chronological split is defined as
All sliding-window samples are generated independently within their corresponding subsets. Any input–target pair crossing a subset boundary is discarded, as is any window containing an imputed value whose construction would require an observation later than the window’s forecast origin.
To improve training stability, min–max normalization is applied after the chronological split. The normalization parameters are calculated exclusively from the training data:
where
and
are computed globally from all valid training observations pooled across the 128 retained GPU devices. A single pair of training-derived normalization parameters is therefore shared by all GPU devices and all forecast horizons. The same parameters are subsequently applied unchanged to the validation and test sets to prevent information leakage.
During model training, the loss is computed on the normalized scale. Before final evaluation, each predicted value is transformed back to the original utilization scale using
where
is the normalized horizon-specific model output and
is the corresponding prediction on the original 0–100% GPU utilization scale. Predictions are not clipped to the physical 0–100% range before metric computation; this avoids artificially improving the reported errors through post-processing. Figures may restrict the displayed vertical axis to the physical utilization range, but all quantitative metrics use the unclipped inverse-normalized predictions. Consequently, the MAE and RMSE are reported in percentage points, while relative error metrics are reported as percentages.
3.4. Multi-Horizon Forecasting Formulation
Based on the chronologically partitioned and normalized 1 min GPU utilization sequences, sliding-window samples are generated independently within the training, validation, and test subsets of each GPU device. For GPU device
m and time step
t, the model input of length
L is
where
is the normalized utilization defined in Equation (
11). Each window contains observations from only one GPU device and one data subset. Windows whose inputs or prediction targets would cross the training, validation, or test boundaries are discarded.
For a forecasting horizon
, the normalized target and its raw-scale counterpart are written consistently as
Thus, the subscript
t denotes the forecast origin, and the superscript
identifies the GPU device and forecast horizon.
This study adopts a direct horizon-specific forecasting strategy. Instead of using one multi-output model for all evaluated lead times, an independent scalar forecasting model is trained for each horizon. For horizon
h, the normalized prediction is
For evaluation,
is transformed back to the original scale using Equation (
12), yielding
.
We use three lead times, , corresponding to 1 min, 10 min, and 1 h forecasts. These horizons cover three operational scales that are relevant to GPU management: immediate reaction, short rolling allocation, and hour-ahead planning. A separate neural model is trained for each lead time, so longer-horizon predictions are not produced recursively from shorter-horizon forecasts. The two deterministic baselines are evaluated separately at the same three lead times.
The look-back window is fixed at , giving every neural model and the rolling mean baseline one hour of recent history at the 1 min sampling rate. This was used as a practical compromise: it includes short bursts as well as slower level changes visible in the traces, without introducing a separate look-back search for every architecture and horizon. The same 60-step context is therefore retained across the comparison. The rolling mean baseline uses this full 60-step history, whereas persistence uses the most recent value at the forecast origin.
3.5. Forecasting Models
To evaluate different sequence-modeling mechanisms for GPU utilization forecasting, five neural forecasting models are compared under the same data and evaluation protocol: 1D-CNN, GRU, FC-LSTM, Liquid Time-Constant Network (LTC), and Transformer. Two deterministic baselines, persistence and rolling mean, are added to provide simple reference forecasts. For readability, the GPU device superscript
is suppressed in the model-specific equations below. For all models, the input is the normalized historical window
where
L is the look-back window length, and the single channel corresponds to normalized GPU utilization. Under the direct horizon-specific formulation, each model outputs one normalized scalar prediction
For each horizon
, an independent neural model is trained; predictions are inverse-normalized before evaluation. The two baselines are deterministic and require no training.
3.5.1. Baseline Models
The two baselines use the same GPU device-specific historical windows, chronological split, eligible forecast targets, and evaluation subsets as the neural models. They have no trainable parameters and therefore do not use the optimization procedure described in
Section 3.6.
For persistence, the most recent normalized utilization value is carried forward to the target horizon:
This baseline is expected to be competitive when utilization is locally stable, but it cannot anticipate a change that occurs after the forecast origin.
The rolling mean baseline uses the same 60-step history as the neural models:
The averaging length is fixed at
before test evaluation rather than selected from test performance. Both baseline predictions are inverse-normalized and scored using the same GPU device-level macro-averaging procedure as the neural models.
3.5.2. 1D-CNN
The 1D-CNN model is used to capture local temporal patterns in GPU utilization traces, such as abrupt spikes, short-term bursts, and transient drops. Given the input window , one-dimensional convolutional filters slide along the temporal dimension to extract local features from neighboring time steps.
The 1D-CNN architecture consists of stacked one-dimensional convolutional layers followed by nonlinear activation functions. Instead of flattening the entire feature map, global average pooling is applied along the temporal dimension to obtain a compact representation of the extracted temporal features. This design reduces the number of parameters in the forecasting head relative to flattening the full feature map and provides a compact temporal representation [
27]. The pooled representation is then passed to a fully connected layer to produce the horizon-specific normalized scalar prediction:
This architecture emphasizes the local temporal structure and permits convolutional feature extraction across the input window. Since the receptive field is determined by the convolutional stack, its relative effectiveness for longer-range dependencies is assessed empirically rather than assumed from the architecture.
3.5.3. GRU
GRU is selected as a lightweight recurrent architecture for sequence forecasting. It uses update and reset gates to regulate hidden-state transitions and control how much historical information is retained or refreshed [
26]. Compared with LSTM, GRU has a more compact gating structure.
For the input window
, the GRU encoder processes the sequence step by step and produces a final hidden representation. This representation is then fed into a fully connected forecasting head to generate the horizon-specific normalized scalar output:
In this comparison, GRU provides a discrete-time recurrent baseline with a compact gating structure. Its behavior under abrupt workload changes is evaluated empirically rather than inferred from the recurrence mechanism alone.
3.5.4. FC-LSTM
FC-LSTM combines an LSTM temporal encoder with fully connected output layers [
9]. The LSTM component captures temporal dependencies through input, forget, and output gates, while the fully connected layers map the final hidden representation to a normalized scalar forecast. The implementation uses the capacity-controlled architecture reported in Table 3, so the primary cross-model comparison is conducted under an approximately common trainable parameter budget.
Given the input sequence
, the LSTM encoder updates its hidden state along the temporal dimension. The final hidden state is used as the temporal representation of the historical window and is passed to a fully connected forecasting head that outputs the normalized horizon-specific prediction:
Compared with GRU, LSTM maintains a separate cell state in addition to the hidden state. FC-LSTM is therefore included as a recurrent architecture with a different memory structure; any performance advantage is assessed from the experimental results rather than assumed from the architecture.
3.5.5. Liquid Time-Constant Network
Liquid Time-Constant Network (LTC) is introduced to evaluate whether continuous-time, input-dependent neural dynamics are suitable for nonstationary GPU utilization forecasting. Different from LSTM and GRU, which update hidden states at discrete time steps, LTC models hidden-state evolution using ordinary differential equations. Therefore, LTC is not a variant of LSTM but a continuous-time recurrent neural network with a different mathematical foundation.
The LTC used in this study is a custom PyTorch implementation of the standard LTC dynamical form [
10]. The implementation uses PyTorch 1.12.1 and
torchdiffeq 0.2.3 [
37] for numerical ODE integration. It does not use the
ncps LTC layer, so the equations and solver settings below correspond directly to the implementation used in the experiments.
For an LTC layer, the hidden state
evolves over continuous time
s. For hidden unit
j,
where
,
is a learnable equilibrium parameter, and
is the base time constant.
The nonlinear gating vector
is parameterized explicitly as
where
,
,
, and
is the element-wise logistic sigmoid. The positive base time constants are parameterized by
while
is learned directly. Thus, the complete trainable parameter set of the LTC dynamics is
.
Equation (
23) defines the effective time constant
The normalized 1 min observations are supplied to the continuous-time dynamics using zero-order hold interpolation:
One ODE time unit corresponds to one minute. Starting from the non-trainable initial state
, the encoder performs 60 consecutive one-minute integrations, so a complete
window corresponds to
. No future observation is used to interpolate the input within an interval.
Each one-minute transition is solved with torchdiffeq.odeint using method=’dopri5’, relative tolerance , and absolute tolerance . The solver uses adaptive internal step sizes; no fixed step_size is supplied and the library’s default adaptive-step controller is retained. Standard odeint, rather than odeint_adjoint, is used.
The final hidden state
is passed to a horizon-specific forecasting head with widths
. The three hidden fully connected layers use ReLU activation and dropout
; the scalar output layer is linear. The resulting forecast is
where
. Dropout is omitted from Equation (
28) for notational clarity and is active only during training.
The exact LTC trainable parameter count is 55,073. The dynamical part contains 16,896 parameters: in , in , 128 in , 128 in , and 128 in . The forecasting head contains 38,177 parameters, giving 16,896 + 38,177 = 55,073 trainable parameters in total. The zero initial state and the integration-time grid are non-trainable.
Because
dopri5 is adaptive, the number of right-hand-side function evaluations (NFE) is input-dependent rather than a fixed model hyperparameter. Every call to the right-hand side of Equation (
23) increments a forward NFE counter. The NFE of one 60-sample input window is the sum of these calls over the 60 one-minute integrations, including evaluations from rejected adaptive steps. Since standard
odeint is used, there is no separate backward ODE re-solve; NFE therefore refers to forward right-hand-side evaluations. The reproducibility implementation logs the per-window NFE and its mean, standard deviation, minimum, and maximum together with the LTC runtime statistics. Across the eligible 1 h test windows, the adaptive solver required
forward right-hand-side evaluations per 60-step input window (mean ± standard deviation), with an observed range of 1188–1512 evaluations. Because the solver is adaptive, NFE varies with the input window and is therefore reported as a distribution rather than a fixed architectural constant.
This formulation provides LTC with a state- and input-dependent dynamical timescale. Its relevance to abrupt spikes, regime transitions, and nonstationary workload patterns is evaluated empirically rather than treated as an a priori performance guarantee [
10].
3.5.6. Transformer
The Transformer model is included to evaluate the effectiveness of self-attention for GPU utilization forecasting [
28]. Unlike recurrent models, Transformer does not process the input sequence strictly step by step. Instead, its self-attention mechanism directly computes dependencies among different time steps within the input window, allowing the model to capture temporal relationships over the entire look-back range.
For the input window
, positional encoding is added to preserve temporal order information. The encoded sequence is then processed by Transformer encoder layers. The resulting temporal representation is aggregated and passed to a fully connected forecasting head to produce the horizon-specific normalized scalar prediction:
The Transformer provides a non-recurrent self-attention architecture that can represent dependencies across the full look-back window. Its relative performance can depend on the data regime, horizon, and model configuration; therefore, it is evaluated under the same protocol as the recurrent and convolutional alternatives without assuming an a priori ranking.
3.6. Training Configuration
The same data split, input history, target definition, and optimization loss are used across the five neural model families, where these choices are architecture-independent. For each , a separate scalar-output neural model is trained, so the three horizons correspond to independent optimization runs rather than a single multi-output network. Persistence and rolling mean require no training or parameter optimization. Architecture-specific choices—for example, the attention dimension or ODE integration—remain model-dependent.
For horizon
h, the mean squared error on the normalized scale is used as the training loss:
where
is the number of pooled training samples available for horizon
h,
is the normalized
h-step-ahead target, and
is the corresponding normalized prediction. Final evaluation metrics are calculated after inverse normalization on the original 0–
utilization scale.
The weighting implicit in the training objective differs from the GPU device macro-averaging used for the reported evaluation metrics. In the implementation, all eligible training windows from the retained GPU devices are placed in one pooled training set, the pooled list is shuffled at the start of each epoch, and ordinary mini-batches of size 128 are drawn from this shuffled list. No GPU device-balanced sampler and no inverse-frequency device weighting are applied. Therefore, if
denotes the number of eligible training windows contributed by GPU device
m at horizon
h, the effective training weight of this device is
Equivalently, the pooled objective can be written as
Thus, a GPU device with more valid training windows has a proportionally greater influence on parameter optimization. This window-weighted training objective is now stated explicitly and is distinguished from evaluation, where each eligible GPU device receives equal weight through the macro-averaging definitions in Equations (
34) and (
45).
The observed distribution of valid training-window counts across the 128 retained GPU devices is summarized in
Table 2. The distribution confirms that the devices contribute unequal numbers of windows to the pooled objective: the median retained device contributes roughly 45,000 training windows, whereas the largest contributes roughly 90,000.
Optimization uses Adam [
38]. Validation data are used only to decide when to stop training and which checkpoint to retain; the test set is not used for model selection. The settings in
Table 3 and
Table 4 are fixed before the final evaluation rather than obtained from an exhaustive search. The input length, chronological split, normalization, loss, optimizer, batch size, and evaluation metrics are shared across the five neural model families. The baselines use the same split, processed histories, eligible targets, and evaluation metrics, but no loss, optimizer, batch size, early stopping, or random seed repetition.
Model capacity is controlled by using the 128-unit LTC configuration (55,073 trainable parameters) as a reference scale, rather than by imposing an exact parameter equality constraint. For each of the other architectures, we selected the nearest practical width that preserved its normal structural requirements. This matters most for the Transformer, whose model dimension must be divisible by the number of attention heads, and for the CNN, whose channel counts change in discrete steps. The final counts lie close together, but this closeness is a consequence of choosing the nearest feasible configurations and not a separately optimized target. The purpose is simply to remove the previous order-of-magnitude capacity difference before comparing the model families.
The resulting parameter counts range only from 55,073 to 55,465, but the comparison should still be regarded as capacity-controlled rather than parameter-identical. The parameter count is only one aspect of model complexity: the FLOPs, memory traffic, recurrent execution, self-attention, and adaptive ODE integration remain different. These differences are retained because removing them would also remove some aspects that distinguish the architectures.
The capacity-controlled 1D-CNN consists of three stacked one-dimensional convolutional layers with 48, 104, and 128 filters, respectively. Each convolutional layer uses a kernel size of 3 and ReLU activation. The extracted temporal feature maps are aggregated using global average pooling rather than flattening, and the pooled representation is mapped to a scalar forecast.
The capacity-controlled GRU uses one recurrent layer with 134 hidden units, followed by a scalar output layer. The capacity-controlled FC-LSTM uses one LSTM layer with 106 hidden units, followed by fully connected layers with 64 and 32 units and the final scalar output. The capacity-controlled Transformer uses sinusoidal positional encoding, 4 attention heads,
,
, and 2 encoder layers. The LTC model uses 128 hidden units with the gating function in Equation (
24), followed by fully connected layers of widths 192, 64, and 16 and a linear scalar output. Its exact trainable parameter count is 55,073. ODE integration uses
torchdiffeq 0.2.3 with adaptive
dopri5, relative tolerance
, and absolute tolerance
.
The detailed training configuration is shown in
Table 4.
Once the model configurations were fixed, each neural model–horizon pair was rerun with five seeds (2021–2025). Neural training remained stochastic because of initialization, minibatch order, and dropout, so the repeated runs are used to report the spread of the primary metrics rather than relying on a single favorable run. The chronological split itself is unchanged across seeds. Because persistence and rolling mean are deterministic, each baseline is evaluated once per horizon on the same eligible test targets.
The 30-percentage-point spike threshold and the 80% high-load threshold are operational diagnostic definitions rather than training hyperparameters. To examine whether the diagnostic conclusions are tied to these exact values, we perform a local sensitivity check using neighboring spike cutoffs of 20, 30, and 40 percentage points and high-load cutoffs of 70%, 80%, and 90%. Model fitting, normalization, the chronological split, and the overall test metrics are unchanged; only the subset definition is recomputed.
The sensitivity analysis shows that stricter thresholds reduce the number of eligible events/targets and increase the absolute error, while the principal RMSE ordering remains unchanged across the neighboring cutoffs. In particular, LTC remains the lowest-RMSE neural model in all three spike threshold settings and all three high-load settings. This supports the interpretation of 30 percentage points and 80% as convenient diagnostic operating points rather than uniquely optimized values.
The fixed diagnostic and robustness parameters are summarized in
Table 5.
The spike-threshold sensitivity results are reported in
Table 6.
The high-load threshold sensitivity results are reported in
Table 7.
The computational environment is summarized in
Table 8.
Training time is measured as the total wall-clock time from the beginning of training until early stopping. Inference latency is measured as the average prediction time per input window on the test set. These measurements are reported to evaluate not only the forecasting accuracy but also practical deployability in near-real-time GPU utilization prediction.
The approximately 55,000-parameter design controls the trainable model size only and is not a claim of equal computational cost. Across the measured runs on the common V100 environment, the total training time falls within the 0.5–3.5 h range and the average single-window inference latency within the 0.5–2.0 ms range reported in
Table 8. The observed inference range is well below the 1 min telemetry interval, so the five primary neural architectures satisfy the timing requirement of the present forecasting setup. Their deployment characteristics nevertheless differ: 1D-CNN and Transformer expose greater within-window parallelism; GRU and FC-LSTM require sequential recurrent updates; and LTC additionally incurs adaptive ODE function evaluations. Parameter matching is therefore interpreted as capacity control rather than compute matching.
Table 9 reports the measured model-specific deployment profile on the common V100 environment. LTC has the largest training and inference cost because of adaptive ODE evaluation, recurrent models are intermediate, and 1D-CNN and Transformer benefit from greater within-window parallelism. For LTC, the ODE right-hand-side call counter is reset for each input window and the forward NFE is logged together with the inference time measurements.
To assess whether the principal numerical differences are consistent across GPU devices, the analysis uses the GPU device as the paired statistical unit. For each comparison, both methods are evaluated on the same eligible targets for each of the 128 retained GPU device streams, and the resulting device-level error values are paired. A two-sided Wilcoxon signed-rank test is used because normality of the paired differences is not assumed. Holm correction is applied within the six prespecified headline comparisons in
Table 10. The five training seeds continue to quantify training repeatability and are not treated as 640 independent observations.
For the primary overall forecasting comparison, each neural model–horizon configuration is trained with five random seeds (2021–2025). For each run, every evaluation metric is computed separately for each eligible GPU device and then macro-averaged according to
Section 3.7.
Table 11 reports the mean and standard deviation of these device-macro metrics across the five runs. The seeds affect training randomness (initialization, batch shuffle, and dropout), while the chronological 70%/15%/15% data split is fixed and seed-independent. The two deterministic baselines are evaluated once on exactly the same eligible GPU device-level targets and are reported as point estimates.
Secondary diagnostic tables are treated as descriptive point estimates unless an uncertainty term is explicitly shown; they are not used to claim statistically significant between-model differences.
Under this paired interpretation, the main conclusion is not that every neural model ranking is statistically distinct. The larger improvements over the simple baselines are supported in the headline comparisons, while the smaller differences among FC-LSTM, LTC, GRU, and Transformer remain numerical rather than inferential claims.
3.7. Evaluation Metrics
We report the MAE, RMSE, WAPE, thresholded SMAPE, and . Predictions are first mapped back to the original 0– utilization scale. Accordingly, the MAE and RMSE are expressed in percentage points, whereas the WAPE and SMAPE are percentages.
Training windows from all retained GPU devices are pooled, but evaluation is not. Accordingly, training is window-weighted according to Equation (
31), whereas the reported metrics are GPU device-macro-averaged. Metrics are computed for each GPU device first and then macro-averaged. This gives each eligible GPU device equal weight even when the valid test sequence lengths differ. The same eligible target indices and macro-averaging rule are used for the two baselines and the five neural models.
Table 11 therefore does
not correspond to a single test vector formed by concatenating all GPU devices.
For horizon h, let denote the set of GPU devices with at least one valid test target, and let be the number of valid test samples for GPU device m. The ground truth and predicted values are denoted by and , respectively.
The GPU device-level mean absolute error is
and the reported MAE is the macro-average
Similarly, the GPU device-level root mean squared error is
and the reported RMSE is
Because GPU utilization traces may contain long idle periods, the conventional MAPE is not used. For each GPU device whose test segment has nonzero total observed utilization, the weighted absolute percentage error is
Let
The reported WAPE is the macro-average
This definition avoids per-sample division by values close to zero while giving each eligible GPU device equal weight.
To further characterize the relative error, a thresholded symmetric mean absolute percentage error is first calculated for each GPU device,
where
percentage points. The reported value is
For
, let
and define the set of GPU devices with nonzero target variance as
For each eligible GPU device,
and the reported coefficient of determination is
Because every reported metric is a macro-average of GPU device-level values, identities that apply to one pooled test vector do not apply to
Table 11. For example, the table should not be used to infer a single target mean from the MAE/WAPE or a single target variance from the RMSE and
.
The MAE and RMSE serve as the main absolute error measures. The WAPE and thresholded SMAPE provide a relative error view, and is included as a secondary fit measure. Given the nonstationary traces and long idle intervals, we do not interpret in isolation.