XPK Start: Sat Apr 18 13:57:17 UTC 2026 PyTorch was not found. Models won't be available and only tokenizers, configuration and file/data utilities can be used. 2026-04-18 13:57:41.634740: E external/local_xla/xla/stream_executor/cuda/cuda_platform.cc:51] failed call to cuInit: INTERNAL: CUDA error: Failed call to cuInit: UNKNOWN ERROR (303) I0418 13:57:42.172078 139863454656320 max_utils.py:273] Attempting to initialize the jax distributed system... I0418 13:57:51.211937 139863454656320 distributed.py:149] Starting JAX distributed service on [::]:8482 I0418 13:57:51.214335 139863454656320 distributed.py:172] Connecting to JAX distributed service on mt-14-async-ckpt-false--crd1p-slice-job-0-0.mt-14-async-ckpt-false--crd1p:8482 I0418 13:57:52.318205 139863454656320 max_utils.py:284] Jax distributed system initialized! I0418 13:57:58.459058 139863454656320 max_utils.py:800] System Information: Jax Version: 0.9.2 I0418 13:57:58.459168 139863454656320 max_utils.py:801] System Information: Jaxlib Version: 0.9.2 I0418 13:57:58.459207 139863454656320 max_utils.py:802] System Information: Jax Backend: PJRT C API TFRT TPU v6 lite Built on Mar 4 2026 11:32:08 (1772652728) cl/878335365 I0418 13:57:58.459240 139863454656320 train_utils.py:348] WARNING: Sequence packing is essentially ignored for synthetic data. Please use a real dataset to use sequence packing. I0418 13:57:59.145299 139863454656320 maxtext_utils.py:1551] Num_devices: 32, shape (1, 1, 1, 32, 1, 1, 1, 1, 1, 1, 1, 1, 1) I0418 13:57:59.145570 139863454656320 checkpointing.py:677] Setting up checkpoint logger... I0418 13:57:59.145623 139863454656320 checkpointing.py:233] Creating checkpoint manager with ocdbt=True and zarr3=True I0418 13:57:59.145667 139863454656320 pytree_checkpoint_handler.py:592] save_device_host_concurrent_bytes=None I0418 13:57:59.146002 139863454656320 base_pytree_checkpoint_handler.py:441] Created BasePyTreeCheckpointHandler: use_ocdbt=True, use_zarr3=True, pytree_metadata_options=PyTreeMetadataOptions(support_rich_types=False), array_metadata_store=<orbax.checkpoint._src.metadata.array_metadata_store.Store object at 0x7f33c7f341a0>, enable_pinned_host_transfer=False, save_concurrent_bytes: 96000000000 (89.4 GiB), restore_concurrent_bytes: 96000000000 (89.4 GiB) I0418 13:58:02.875853 139863454656320 checkpointing.py:265] Enabling policy for fixed interval checkpointing. I0418 13:58:02.876099 139863454656320 checkpoint_manager.py:708] [process=7][thread=MainThread] CheckpointManager init: checkpointers=None, item_names=('items',), item_handlers={'items': <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7f1f8c22eab0>}, handler_registry=None I0418 13:58:02.876332 139863454656320 composite_checkpoint_handler.py:237] Deferred registration for item: "items". Adding handler `<orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7f1f8c22eab0>` for item "items" and save args `<class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeSaveArgs'>` and restore args `<class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeRestoreArgs'>` to `_handler_registry`. I0418 13:58:02.876381 139863454656320 composite_checkpoint_handler.py:237] Deferred registration for item: "metrics". Adding handler `<orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x7f1f8c2d3500>` for item "metrics" and save args `<class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonSaveArgs'>` and restore args `<class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonRestoreArgs'>` to `_handler_registry`. I0418 13:58:02.876416 139863454656320 composite_checkpoint_handler.py:505] Initialized registry DefaultCheckpointHandlerRegistry({('items', <class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeSaveArgs'>): <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7f1f8c22eab0>, ('items', <class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeRestoreArgs'>): <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7f1f8c22eab0>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonSaveArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x7f1f8c2d3500>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonRestoreArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x7f1f8c2d3500>}). I0418 13:58:02.876732 139863454656320 abstract_checkpointer.py:35] orbax-checkpoint version: 0.11.34 I0418 13:58:04.534538 139863454656320 checkpoint_manager.py:1812] Found 0 checkpoint steps in gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints I0418 13:58:05.395153 139863454656320 checkpoint_manager.py:929] [process=7][thread=MainThread] CheckpointManager created, primary_host=0, CheckpointManagerOptions=CheckpointManagerOptions(save_interval_steps=1, max_to_keep=None, keep_time_interval=None, keep_period=None, should_keep_fn=None, best_fn=None, best_mode='max', keep_checkpoints_without_metrics=True, step_prefix=None, step_format_fixed_length=None, step_name_format=None, create=True, cleanup_tmp_directories=False, save_on_steps=frozenset(), single_host_load_and_broadcast=False, todelete_subdir=None, todelete_full_path=None, enable_background_delete=False, read_only=False, enable_async_checkpointing=False, async_options=None, multiprocessing_options=MultiprocessingOptions(primary_host=0, active_processes=None, barrier_sync_key_prefix=None), should_save_fn=None, file_options=FileOptions(path_permission_mode=None), save_root_metadata=True, temporary_path_class=None, save_decision_policy=FixedIntervalPolicy(interval=5), preservation_policy=LatestN(n=None), prevent_write_metrics=False, enable_should_save_is_saving_in_progress_check=True, enable_per_process_directory_creation=False, lightweight_initialize=False), root_directory=gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints: <orbax.checkpoint.checkpoint_manager.CheckpointManager object at 0x7f1f8c2cec60> I0418 13:58:05.395318 139863454656320 checkpointing.py:301] Checkpoint manager created! I0418 13:58:06.323900 139863454656320 nnx_wrappers.py:437] Unknown Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_norm_length', 'activation_embed'). I0418 13:58:06.324017 139863454656320 nnx_wrappers.py:437] Unknown Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None). I0418 13:58:06.701155 139863454656320 attentions.py:1088] attentions/inputs_q Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed'). I0418 13:58:06.701244 139863454656320 attentions.py:1088] attentions/inputs_q Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None). I0418 13:58:06.717560 139863454656320 attentions.py:1089] attentions/inputs_kv Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed'). I0418 13:58:06.717618 139863454656320 attentions.py:1089] attentions/inputs_kv Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None). I0418 13:58:06.741804 139863454656320 attentions.py:1154] attentions/query Logical: bfloat16[32,2048,16,128].................................... ('activation_kv_batch', 'activation_attn_length', 'activation_kv_heads', 'activation_kv_head_dim'). I0418 13:58:06.741876 139863454656320 attentions.py:1154] attentions/query Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0418 13:58:06.758205 139863454656320 attentions.py:1155] attentions/key Logical: bfloat16[32,2048,16,128].................................... ('activation_kv_batch', 'activation_attn_length', 'activation_kv_heads', 'activation_kv_head_dim'). I0418 13:58:06.758266 139863454656320 attentions.py:1155] attentions/key Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0418 13:58:06.774576 139863454656320 attentions.py:1156] attentions/value Logical: bfloat16[32,2048,16,128].................................... ('activation_kv_batch', 'activation_attn_length', 'activation_kv_heads', 'activation_kv_head_dim'). I0418 13:58:06.774637 139863454656320 attentions.py:1156] attentions/value Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0418 13:58:06.799065 139863454656320 attentions.py:1197] attentions/out Logical: bfloat16[32,2048,16,128].................................... ('activation_batch', 'activation_attn_length', 'activation_heads', 'activation_kv'). I0418 13:58:06.799145 139863454656320 attentions.py:1197] attentions/out Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0418 13:58:06.820020 139863454656320 linears.py:525] linears/x Logical: bfloat16[32,2048,7168]...................................... ('activation_batch', 'activation_length', 'activation_mlp'). I0418 13:58:06.820106 139863454656320 linears.py:525] linears/x Physical: bfloat16[32,2048,7168]...................................... ('fsdp', None, None). I0418 13:58:07.040901 139863454656320 checkpointing.py:577] checkpoint manager exists so trying to load this run's existing checkpoint I0418 13:58:07.041012 139863454656320 checkpointing.py:665] No existing checkpoints found, not restoring checkpoint. fsdp: 32 I0418 13:58:08.465531 139863454656320 maxtext_utils.py:1654] params/params/decoder/decoder_norm/scale Shape: float32[2048] Logical: P('norm',) Physical: (None,) I0418 13:58:08.465653 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/mlp/wi_0/kernel Shape: float32[2048,16,7168] Logical: P('embed', 'layers', 'mlp') Physical: ('fsdp', None, None) I0418 13:58:08.465706 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/mlp/wi_1/kernel Shape: float32[2048,16,7168] Logical: P('embed', 'layers', 'mlp') Physical: ('fsdp', None, None) I0418 13:58:08.465761 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/mlp/wo/kernel Shape: float32[7168,16,2048] Logical: P('mlp', 'layers', 'embed') Physical: (None, None, 'fsdp') I0418 13:58:08.465837 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/post_self_attention_layer_norm/scale Shape: float32[2048,16] Logical: P('norm', 'layers') Physical: (None, None) I0418 13:58:08.465881 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/pre_self_attention_layer_norm/scale Shape: float32[2048,16] Logical: P('norm', 'layers') Physical: (None, None) I0418 13:58:08.465934 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/self_attention/key/kernel Shape: float32[2048,16,16,128] Logical: P('embed', 'layers', 'kv_heads', 'kv_head_dim') Physical: ('fsdp', None, None, None) I0418 13:58:08.465984 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/self_attention/out/kernel Shape: float32[16,16,128,2048] Logical: P('heads', 'layers', 'kv', 'embed') Physical: (None, None, None, 'fsdp') I0418 13:58:08.466021 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/self_attention/query/kernel Shape: float32[2048,16,16,128] Logical: P('embed', 'layers', 'q_heads', 'kv') Physical: ('fsdp', None, None, None) I0418 13:58:08.466056 139863454656320 maxtext_utils.py:1654] params/params/decoder/layers/self_attention/value/kernel Shape: float32[2048,16,16,128] Logical: P('embed', 'layers', 'kv_heads', 'kv_head_dim') Physical: ('fsdp', None, None, None) I0418 13:58:08.466122 139863454656320 maxtext_utils.py:1654] params/params/decoder/logits_dense/kernel Shape: float32[2048,32000] Logical: P('embed_vocab', 'vocab') Physical: ('fsdp', None) I0418 13:58:08.466172 139863454656320 maxtext_utils.py:1654] params/params/token_embedder/embedding Shape: float32[32000,2048] Logical: P('vocab', 'embed_vocab') Physical: (None, 'fsdp') I0418 13:58:08.958178 139863454656320 train.py:155] train/xent Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length'). I0418 13:58:08.958285 139863454656320 train.py:155] train/xent Physical: float32[32,2048]............................................ ('fsdp', None). I0418 13:58:08.974035 139863454656320 train.py:162] train/z_loss Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length'). I0418 13:58:08.974113 139863454656320 train.py:162] train/z_loss Physical: float32[32,2048]............................................ ('fsdp', None). I0418 13:58:20.029820 139863454656320 max_utils.py:791] Total memory size: 1.5 GB, Output size: 0.4 GB, Temp size: 1.1 GB, Argument size: 0.4 GB, Host temp size: 0.0 GB. I0418 13:58:20.030607 139863454656320 metric_logger.py:301] number parameters: 1.104 billion I0418 13:58:31.552190 139863454656320 checkpointing.py:772] Waiting for step 0 to finish before checkpoint... I0418 13:58:31.705682 139863454656320 checkpointing.py:776] Waited 0.1534709930419922 seconds for step 0 to finish before starting checkpointing. I0418 13:58:31.708294 139863454656320 checkpoint_manager.py:2009] [process=7][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0418 13:58:31.710010 139863454656320 checkpoint_manager.py:1512] [process=7] Saving checkpoint at step 0 I0418 13:58:31.711494 139863454656320 event_tracking.py:70] [process=7] [sync] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/0. I0418 13:58:35.392191 139863454656320 signaling_client.py:364] Using JaxDistributedSignalingClient I0418 13:58:35.393493 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=1] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 13:58:37.207227 139863454656320 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array. I0418 13:58:37.207324 139863454656320 replica_slices.py:424] Transferring arrays to host memory with options: use_replica_parallel=True, min_slice_bytes_for_replica_parallel=None, max_replicas_for_replica_parallel=None, enable_pinned_host_transfer=False I0418 13:58:37.481436 139863454656320 base_pytree_checkpoint_handler.py:154] [process=7][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.275561s I0418 13:58:37.490503 139863454656320 base_pytree_checkpoint_handler.py:130] [process=7] /jax/orbax/write/blocking_gbytes_per_sec: 5.318 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.2900733947753906 s) (per-host) I0418 13:58:37.490583 139863454656320 base_pytree_checkpoint_handler.py:768] [process=7][thread=MainThread] Initiated Pytree async_save. Time taken: 0.290170s (batch_requests_ready=0.002349s, total_serialization_initiated=0.287711s, others=0.000110s) I0418 13:58:37.490696 139863454656320 composite_checkpoint_handler.py:715] [process=7][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 2.098639s (all_items=0.000037s, per_item={'items': '0.00003743'}, temp_paths=2.098602) I0418 13:58:37.490749 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=1] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 13:58:37.490794 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=1] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 13:58:37.495063 2815 google_auth_provider.cc:181] Running on GCE, using service account 562977990677-compute@developer.gserviceaccount.com I0418 13:58:40.374265 139733869180672 array_metadata_store.py:203] [process=7][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/0/items/array_metadatas/process_7 I0418 13:59:11.916063 139863454656320 base_pytree_checkpoint_handler.py:130] [process=7] /jax/orbax/write/gbytes_per_sec: 45.501 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 34.715601205825806 s) (per-host) I0418 13:59:16.673740 139863454656320 event_tracking.py:125] [process=7] [sync] Finished blocking save in 44.96 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/0. I0418 13:59:21.188954 139863454656320 event_tracking.py:138] [process=7] [sync] Finished save in 49.48 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/0 I0418 13:59:21.191475 139863454656320 checkpoint_manager.py:2137] [process=7][thread=MainThread][step=0] CheckpointManager Save Finalize is syncing with other hosts... I0418 13:59:21.193472 139863454656320 checkpoint_manager.py:2146] [process=7][thread=MainThread][step=0] CheckpointManager Save Finalize is done on all hosts. I0418 13:59:21.193524 139863454656320 checkpoint_manager.py:1581] [process=7][thread=MainThread][step=0] Finished synchronous save. I0418 13:59:21.193580 139863454656320 standard_logger.py:34] {'step': 0, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': True, 'wait_for_prev_start_time': 1776520711.7082748, 'wait_for_prev_duration_secs': 6.151199340820312e-05, 'time_between_consecutive_saves_sec': None, 'checkpointer_blocking_start_time': 1776520711.7100475, 'checkpointer_blocking_duration_secs': 49.47904419898987, 'get_old_steps_start_time': 1776520761.1891148, 'get_old_steps_duration_secs': 3.62396240234375e-05, 'checkpoint_manager_blocking_start_time': 1776520711.7062197, 'checkpoint_manager_blocking_duration_secs': 49.48733115196228} I0418 13:59:21.193665 139863454656320 checkpointing.py:410] Saved a checkpoint at step 0. I0418 13:59:21.193710 139863454656320 max_utils.py:750] Memstats: After params initialized: I0418 13:59:21.193758 139863454656320 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_26(process=7,(2,6,0,0)) I0418 13:59:21.193788 139863454656320 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_27(process=7,(3,6,0,0)) I0418 13:59:21.193813 139863454656320 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_30(process=7,(2,7,0,0)) I0418 13:59:21.193836 139863454656320 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_31(process=7,(3,7,0,0)) I0418 13:59:21.519658 139863454656320 metric_logger.py:196] completed step: 0, seconds: 11.521, TFLOP/s/device: 1.179, Tokens/s/device: 177.755, total_weights: 65536, loss: 10.874, lm_loss: 10.874, perplexity: 52779.875 I0418 13:59:21.676695 139863454656320 metric_logger.py:196] completed step: 1, seconds: 49.951, TFLOP/s/device: 0.272, Tokens/s/device: 41.000, total_weights: 65536, loss: 10.874, lm_loss: 10.874, perplexity: 52779.875 I0418 13:59:22.081700 139863454656320 metric_logger.py:196] completed step: 2, seconds: 0.025, TFLOP/s/device: 543.811, Tokens/s/device: 81969.182, total_weights: 65536, loss: 10.560, lm_loss: 10.560, perplexity: 38547.719 I0418 13:59:22.229309 139863454656320 metric_logger.py:196] completed step: 3, seconds: 0.405, TFLOP/s/device: 33.509, Tokens/s/device: 5050.829, total_weights: 65536, loss: 9.980, lm_loss: 9.980, perplexity: 21590.506 I0418 13:59:22.233797 139863454656320 checkpointing.py:772] Waiting for step 5 to finish before checkpoint... I0418 13:59:22.523565 139863454656320 checkpointing.py:776] Waited 0.28973388671875 seconds for step 5 to finish before starting checkpointing. I0418 13:59:22.526371 139863454656320 checkpoint_manager.py:2009] [process=7][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0418 13:59:22.528033 139863454656320 checkpoint_manager.py:1512] [process=7] Saving checkpoint at step 5 I0418 13:59:22.529738 139863454656320 event_tracking.py:70] [process=7] [sync] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/5. I0418 13:59:25.433465 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=2] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 13:59:27.217209 139863454656320 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array. I0418 13:59:27.217308 139863454656320 replica_slices.py:424] Transferring arrays to host memory with options: use_replica_parallel=True, min_slice_bytes_for_replica_parallel=None, max_replicas_for_replica_parallel=None, enable_pinned_host_transfer=False I0418 13:59:27.261765 139863454656320 base_pytree_checkpoint_handler.py:154] [process=7][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.045650s I0418 13:59:27.261956 139863454656320 base_pytree_checkpoint_handler.py:130] [process=7] /jax/orbax/write/blocking_gbytes_per_sec: 30.862 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.04998302459716797 s) (per-host) I0418 13:59:27.262014 139863454656320 base_pytree_checkpoint_handler.py:768] [process=7][thread=MainThread] Initiated Pytree async_save. Time taken: 0.050050s (batch_requests_ready=0.002081s, total_serialization_initiated=0.047893s, others=0.000076s) I0418 13:59:27.262131 139863454656320 composite_checkpoint_handler.py:715] [process=7][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 1.829850s (all_items=0.000030s, per_item={'items': '0.00003004'}, temp_paths=1.829820) I0418 13:59:27.262176 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=2] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 13:59:27.262215 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=2] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 13:59:29.773536 139733869180672 array_metadata_store.py:203] [process=7][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/5/items/array_metadatas/process_7 I0418 14:00:05.915826 139863454656320 base_pytree_checkpoint_handler.py:130] [process=7] /jax/orbax/write/gbytes_per_sec: 40.812 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 38.70381569862366 s) (per-host) I0418 14:00:11.070692 139863454656320 event_tracking.py:125] [process=7] [sync] Finished blocking save in 48.54 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/5. I0418 14:00:15.826430 139863454656320 event_tracking.py:138] [process=7] [sync] Finished save in 53.30 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/5 I0418 14:00:15.829177 139863454656320 checkpoint_manager.py:2137] [process=7][thread=MainThread][step=5] CheckpointManager Save Finalize is syncing with other hosts... I0418 14:00:15.830801 139863454656320 checkpoint_manager.py:2146] [process=7][thread=MainThread][step=5] CheckpointManager Save Finalize is done on all hosts. I0418 14:00:15.830851 139863454656320 checkpoint_manager.py:1581] [process=7][thread=MainThread][step=5] Finished synchronous save. I0418 14:00:15.830905 139863454656320 standard_logger.py:34] {'step': 5, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': True, 'wait_for_prev_start_time': 1776520762.5263367, 'wait_for_prev_duration_secs': 0.00012087821960449219, 'time_between_consecutive_saves_sec': 1.3328242301940918, 'checkpointer_blocking_start_time': 1776520762.5280926, 'checkpointer_blocking_duration_secs': 53.29847574234009, 'get_old_steps_start_time': 1776520815.8265877, 'get_old_steps_duration_secs': 2.5033950805664062e-05, 'checkpoint_manager_blocking_start_time': 1776520762.5241828, 'checkpoint_manager_blocking_duration_secs': 53.30669593811035} I0418 14:00:15.830993 139863454656320 checkpointing.py:410] Saved a checkpoint at step 5. I0418 14:00:15.831895 139863454656320 metric_logger.py:196] completed step: 4, seconds: 0.153, TFLOP/s/device: 88.991, Tokens/s/device: 13413.764, total_weights: 65536, loss: 9.460, lm_loss: 9.460, perplexity: 12840.355 I0418 14:00:15.854629 139863454656320 metric_logger.py:196] completed step: 5, seconds: 0.148, TFLOP/s/device: 91.995, Tokens/s/device: 13866.414, total_weights: 65536, loss: 8.959, lm_loss: 8.959, perplexity: 7776.467 I0418 14:00:39.550851 139863454656320 metric_logger.py:196] completed step: 6, seconds: 53.603, TFLOP/s/device: 0.253, Tokens/s/device: 38.207, total_weights: 65536, loss: 8.469, lm_loss: 8.469, perplexity: 4762.740 I0418 14:00:39.698407 139863454656320 metric_logger.py:196] completed step: 7, seconds: 23.567, TFLOP/s/device: 0.577, Tokens/s/device: 86.902, total_weights: 65536, loss: 8.003, lm_loss: 8.003, perplexity: 2989.151 I0418 14:00:39.846139 139863454656320 metric_logger.py:196] completed step: 8, seconds: 0.152, TFLOP/s/device: 89.203, Tokens/s/device: 13445.643, total_weights: 65536, loss: 7.572, lm_loss: 7.572, perplexity: 1943.098 I0418 14:00:39.992759 139863454656320 checkpointing.py:772] Waiting for step 9 to finish before checkpoint... I0418 14:00:39.993466 139863454656320 checkpointing.py:776] Waited 0.0007288455963134766 seconds for step 9 to finish before starting checkpointing. I0418 14:00:39.995513 139863454656320 checkpoint_manager.py:2009] [process=7][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0418 14:00:39.997547 139863454656320 checkpoint_manager.py:1512] [process=7] Saving checkpoint at step 9 I0418 14:00:39.999037 139863454656320 event_tracking.py:70] [process=7] [sync] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/9. I0418 14:00:43.027107 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=3] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 14:00:44.443551 139863454656320 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array. I0418 14:00:44.443647 139863454656320 replica_slices.py:424] Transferring arrays to host memory with options: use_replica_parallel=True, min_slice_bytes_for_replica_parallel=None, max_replicas_for_replica_parallel=None, enable_pinned_host_transfer=False I0418 14:00:44.488842 139863454656320 base_pytree_checkpoint_handler.py:154] [process=7][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.046448s I0418 14:00:44.489020 139863454656320 base_pytree_checkpoint_handler.py:130] [process=7] /jax/orbax/write/blocking_gbytes_per_sec: 30.681 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.050278425216674805 s) (per-host) I0418 14:00:44.489091 139863454656320 base_pytree_checkpoint_handler.py:768] [process=7][thread=MainThread] Initiated Pytree async_save. Time taken: 0.050344s (batch_requests_ready=0.001984s, total_serialization_initiated=0.048290s, others=0.000070s) I0418 14:00:44.493950 139863454656320 composite_checkpoint_handler.py:715] [process=7][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 1.468234s (all_items=0.000023s, per_item={'items': '0.00002265'}, temp_paths=1.468211) I0418 14:00:44.494014 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=3] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 14:00:44.494056 139863454656320 future.py:372] [process=7][thread=MainThread][operation_id=3] _SignalingThread.join() waiting for signals ([]) blocking the main thread will slow down blocking save times. This is likely due to main thread calling result() on a CommitFuture. I0418 14:00:47.439800 139738654873344 array_metadata_store.py:203] [process=7][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/9/items/array_metadatas/process_7 I0418 14:01:23.540135 139863454656320 base_pytree_checkpoint_handler.py:130] [process=7] /jax/orbax/write/gbytes_per_sec: 40.398 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 39.10133457183838 s) (per-host) I0418 14:01:28.531048 139863454656320 event_tracking.py:125] [process=7] [sync] Finished blocking save in 48.53 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/9. I0418 14:01:32.449393 139863454656320 event_tracking.py:138] [process=7] [sync] Finished save in 52.45 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints/9 I0418 14:01:32.451371 139863454656320 checkpoint_manager.py:2137] [process=7][thread=MainThread][step=9] CheckpointManager Save Finalize is syncing with other hosts... I0418 14:01:32.453262 139863454656320 checkpoint_manager.py:2146] [process=7][thread=MainThread][step=9] CheckpointManager Save Finalize is done on all hosts. I0418 14:01:32.453319 139863454656320 checkpoint_manager.py:1581] [process=7][thread=MainThread][step=9] Finished synchronous save. I0418 14:01:32.453376 139863454656320 standard_logger.py:34] {'step': 9, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260418_125719/linen_xpk_main_20260418_125719_14_async_ckpt_false/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': True, 'wait_for_prev_start_time': 1776520839.995496, 'wait_for_prev_duration_secs': 5.5789947509765625e-05, 'time_between_consecutive_saves_sec': 24.164656400680542, 'checkpointer_blocking_start_time': 1776520839.9975848, 'checkpointer_blocking_duration_secs': 52.45193028450012, 'get_old_steps_start_time': 1776520892.4495273, 'get_old_steps_duration_secs': 2.1696090698242188e-05, 'checkpoint_manager_blocking_start_time': 1776520839.9936848, 'checkpoint_manager_blocking_duration_secs': 52.4596643447876} I0418 14:01:32.453481 139863454656320 checkpointing.py:410] Saved a checkpoint at step 9. I0418 14:01:32.453522 139863454656320 checkpoint_manager.py:2009] [process=7][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0418 14:01:32.453553 139863454656320 checkpoint_manager.py:2009] [process=7][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0418 14:01:32.454246 139863454656320 metric_logger.py:196] completed step: 9, seconds: 0.148, TFLOP/s/device: 92.116, Tokens/s/device: 13884.652, total_weights: 65536, loss: 7.181, lm_loss: 7.181, perplexity: 1314.495 Per train step: Total TFLOPs: 13.59 split as 93.93% learnable weight flops and 6.07% attention flops XPK End: Sat Apr 18 14:01:43 UTC 2026 EXIT_CODE=0