tensorflow/models · error · ValueError

The l2_weight_decay cannot be used together with lars optimi

Error message

The l2_weight_decay cannot be used together with lars optimizer. Please set it to 0.

What it means

Error "The l2_weight_decay cannot be used together with lars optimizer. Please set it to 0." thrown in tensorflow/models.

Source

Thrown at official/projects/simclr/tasks/simclr.py:68

@task_factory.register_task_cls(exp_cfg.SimCLRPretrainTask)
class SimCLRPretrainTask(base_task.Task):
  """A task for image classification."""

  def create_optimizer(self,
                       optimizer_config: OptimizationConfig,
                       runtime_config: Optional[RuntimeConfig] = None):
    """Creates an TF optimizer from configurations.

    Args:
      optimizer_config: the parameters of the Optimization settings.
      runtime_config: the parameters of the runtime.

    Returns:
      A tf.optimizers.Optimizer object.
    """
    if (optimizer_config.optimizer.type == 'lars' and
        self.task_config.loss.l2_weight_decay > 0.0):
      raise ValueError('The l2_weight_decay cannot be used together with lars '
                       'optimizer. Please set it to 0.')

    opt_factory = optimization.OptimizerFactory(optimizer_config)
    optimizer = opt_factory.build_optimizer(opt_factory.build_learning_rate())
    # Configuring optimizer when loss_scale is set in runtime config. This helps
    # avoiding overflow/underflow for float16 computations.
    if runtime_config and runtime_config.loss_scale:
      optimizer = performance.configure_optimizer(
          optimizer,
          use_float16=runtime_config.mixed_precision_dtype == 'float16',
          loss_scale=runtime_config.loss_scale)

    return optimizer

  def build_model(self):
    model_config = self.task_config.model
    input_specs = tf_keras.layers.InputSpec(shape=[None] +
                                            model_config.input_size)

View on GitHub (pinned to e006f5f0d5)

When it happens

Trigger: Thrown at official/projects/simclr/tasks/simclr.py:68 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of tensorflow/models@e006f5f0d5 (2026-08-24). Data as JSON: /api/errors/0cc24094d952df88. Report an issue: GitHub.