> ## Documentation Index > Fetch the complete documentation index at: https://sambanova-systems.mintlify.site/docs/llms.txt > Use this file to discover all available pages before exploring further. # PEF A PEF (Processor Executable Format) is the compiled artifact for one model configuration. A `Pef` resource registers one such executable together with the metadata describing what it supports, including its model architecture, batch size, and maximum sequence length. A [ModelProfile](/docs/en/sambastack/service-administration/model-deployment/custom-resources/model-profile) selects which PEF, sequence size, and batch size are used, so in a bundle or a deployment you reference a profile rather than an individual PEF. Author `Pef` resources only when introducing a model architecture that SambaStack does not yet support. `Pef` resources use `apiVersion: sambanova.ai/v1alpha1`. ## Structure ```yaml theme={} apiVersion: sambanova.ai/v1alpha1 kind: Pef metadata: name: llama-4-maverick-ss131072-bs1 spec: metadata: model_arch: llama-4-maverick batch_size: 1 max_seq_length: 131072 max_completion_tokens: 131072 job_type: infer num_rdus: 16 rdu_arch: SN40L-16 task_name: mllama continuous_batching: false use_context_cache: false constrained_decoding: false is_spec_prefill: false versions: "1": source: gs:///path/to/model.pef cached_path: gs:///path/to/model.pef ckpt_sharing_uuid: c5f61b8d9a1f41ed02b7d5d6098f6abc pef_status: stable num_tokens_at_a_time: 20 prefill_graphs: - 131072 vision_embedding_pef: gs:///path/to/vision.pef vision_embedding_pef_cached_path: gs:///path/to/vision.pef owner: no-reply@sambanova.ai secretName: sambanova-artifact-reader ``` ### Identity and shape | Field | Required | Description | | ------------------------------------------------------------- | -------- | ----------------------------------------------------------------------------------------------- | | `spec.metadata.model_arch` | Yes | Architecture of this PEF, which determines the checkpoints that the PEF is compatible with. | | `spec.metadata.batch_size` | Yes | Batch size that the PEF was compiled for. | | `spec.metadata.max_seq_length` | Yes | Maximum sequence length that the PEF supports. | | `spec.metadata.max_completion_tokens` | Yes | Maximum number of completion tokens the PEF supports. Must equal `max_seq_length`. | | `spec.metadata.job_type` | No | Whether the PEF is compiled for inference or training, for example `infer`. | | `spec.metadata.num_rdus`, `spec.metadata.rdu_arch` | No | Number of RDUs and the RDU architecture that the PEF was compiled for, for example `SN40L-16`. | | `spec.metadata.task_name` | No | Task in the app driver this PEF uses. Defaults to the text generation task when unset. | | `spec.metadata.mapping`, `spec.metadata.mixed_precision_mode` | No | Compilation settings recorded for traceability: the mapping used, and the mixed precision mode. | | `spec.metadata.vocab_size` | No | Vocabulary size the PEF was compiled for. | | `spec.metadata.pef_version` | No | Version of the PEF protocol this PEF was compiled against. | ### Feature support flags These values determine the `features` list of the profiles built from this PEF. | Field | Required | Description | | ------------------------------------------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `spec.metadata.continuous_batching` | No | Whether the PEF supports continuous batching. Defaults to `false`. | | `spec.metadata.use_context_cache` | No | Whether the PEF supports and uses prompt caching. Defaults to `false`. | | `spec.metadata.constrained_decoding` | No | Whether the PEF supports constrained decoding. Defaults to `false`. | | `spec.metadata.is_spec_prefill` | No | Whether the PEF can be used as a speculator for speculative prefill. Defaults to `false`. | | `spec.metadata.cache_batch_size`, `spec.metadata.decode_batch_size` | No | Cache and decode batch sizes used for continuous batching. | | `spec.metadata.k` | No | The `k` value used for a speculative decoding **target** model PEF, under the two-expert draft/target scheme. | | `spec.metadata.mtp_weight_category` | No | Weight category the PEF's fused multi-token prediction drafter was compiled with, for example `GEMMA4_MTP_WEIGHT`. Set only on single-PEF MTP PEFs, whose drafter weights are overlaid from a separate drafter checkpoint at load time. Distinct from `k`. | | `spec.metadata.dynamic_dims` | No | Dynamic dimensions available in this PEF, such as `batch_size` and the sequence length dimensions. | | `spec.metadata.vision_dynamic_dims` | No | Dynamic dimensions available for the PEF's vision component, for multimodal models. | ### Versions Each key under `spec.versions` is a version string, and its value describes one build of the PEF. | Field | Required | Description | | ----------------------------------------------------------------------------------------------------------------------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | `spec.versions..source` | Yes | Location to download this version of the PEF from. | | `spec.versions..cached_path` | Yes | Path to this PEF as cached in the legalizer database. Path substitution does not affect this value. | | `spec.versions..ckpt_sharing_uuid` | Yes | Identifier that defines checkpoint-sharing relationships. PEFs with the same identifier can share a checkpoint. | | `spec.versions..pef_status` | Yes | Lifecycle status of this PEF version. Defaults to `preview`. See [PEF and checkpoint lifecycle status](#pef-and-checkpoint-lifecycle-status). | | `spec.versions..prefill_graphs` | No | Discrete prefill lengths compiled into this version. Combined with `metadata.dynamic_dims` to compute the prompt sizes the version advertises for gateway batching-queue routing, which surface as `promptBatchingBuckets` on a profile. Left unset when it cannot be derived. | | `spec.versions..num_tokens_at_a_time` | No | Number of tokens generated on each call to the PEF. | | `spec.versions..copy_pef` | No | Source path for the copy PEF. | | `spec.versions..vision_embedding_pef`, `spec.versions..vision_embedding_pef_cached_path` | No | Source and cached paths for the companion vision embedding PEF, used by multimodal models. | | `spec.versions..pef_name_override`, `spec.versions..copy_pef_name_override`, `spec.versions..vision_embedding_pef_name_override` | No | Name overrides retained for backward compatibility. | ### Ownership and access | Field | Required | Description | | ----------------- | -------- | --------------------------------------------------------------------- | | `spec.owner` | Yes | Owner of the PEF. | | `spec.secretName` | Yes | Name of the single secret required in order to download the artifact. | `spec.metadata.seq_lengths` no longer exists. The sequence lengths a PEF serves are now derived from `metadata.max_seq_length` together with `metadata.dynamic_dims` and the version's `prefill_graphs`. ## PEF and checkpoint lifecycle status SambaStack assigns a `pef_status` field to PEF CR versions and a `checkpoint_status` field to model CR checkpoint versions to indicate their support lifecycle. Understanding these statuses helps you make informed decisions when selecting PEF or checkpoint versions. **PEF and checkpoint version status values** Each version entry in a PEF CR includes a `pef_status` field. Model CR checkpoint versions use `checkpoint_status`. Both share the same set of values: | Status | Description | | ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | `preview` | Not fully tested or supported. May have unknown reliability or performance issues, or limited functionality (for example, partial function calling support). Not recommended for production workloads. | | `stable` | Fully supported and tested. | | `deprecated` | Has known reliability or performance issues. Still available for a limited transition period (up to 3 months from the deprecation announcement) to allow migration to a stable version. | | `removed` | No longer usable. The version entry is retained in the PEF CR or model CR for traceability and auditability, but the path may no longer exist, causing deployment to fail if referenced. | **Example PEF CR versions with status** ```yaml theme={} versions: '1': source: gs://ext-sambastack-artifacts-prod-0/path/to/pef_v1.pef pef_status: deprecated '2': source: gs://ext-sambastack-artifacts-prod-0/path/to/pef_v2.pef pef_status: stable ``` To check version statuses, run `kubectl describe pef ` or `kubectl describe model ` and review the `pef_status` or `checkpoint_status` field in the `Versions` section. ## Related resources Groups feature-compatible PEFs for one model architecture How PEFs, profiles, models, bundles, and deployments fit together