XPK Start: Sun Apr 19 19:08:38 UTC 2026 PyTorch was not found. Models won't be available and only tokenizers, configuration and file/data utilities can be used. 2026-04-19 19:09:02.212274: 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) I0419 19:09:02.750988 133985913878336 max_utils.py:273] Attempting to initialize the jax distributed system... I0419 19:09:11.790984 133985913878336 distributed.py:149] Starting JAX distributed service on [::]:8482 I0419 19:09:11.793567 133985913878336 distributed.py:172] Connecting to JAX distributed service on mt-14-async-ckpt-false--470ry-slice-job-0-0.mt-14-async-ckpt-false--470ry:8482 I0419 19:09:13.210495 133985913878336 max_utils.py:284] Jax distributed system initialized! I0419 19:09:19.383217 133985913878336 max_utils.py:800] System Information: Jax Version: 0.9.2 I0419 19:09:19.383317 133985913878336 max_utils.py:801] System Information: Jaxlib Version: 0.9.2 I0419 19:09:19.383357 133985913878336 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 I0419 19:09:19.383398 133985913878336 train_utils.py:348] WARNING: Sequence packing is essentially ignored for synthetic data. Please use a real dataset to use sequence packing. I0419 19:09:20.079373 133985913878336 maxtext_utils.py:1551] Num_devices: 32, shape (1, 1, 1, 32, 1, 1, 1, 1, 1, 1, 1, 1, 1) I0419 19:09:20.079662 133985913878336 checkpointing.py:677] Setting up checkpoint logger... I0419 19:09:20.079716 133985913878336 checkpointing.py:233] Creating checkpoint manager with ocdbt=True and zarr3=True I0419 19:09:20.079762 133985913878336 pytree_checkpoint_handler.py:592] save_device_host_concurrent_bytes=None I0419 19:09:20.080099 133985913878336 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 0x79db68d181d0>, enable_pinned_host_transfer=False, save_concurrent_bytes: 96000000000 (89.4 GiB), restore_concurrent_bytes: 96000000000 (89.4 GiB) I0419 19:09:21.556690 133985913878336 checkpointing.py:265] Enabling policy for fixed interval checkpointing. I0419 19:09:21.556939 133985913878336 checkpoint_manager.py:708] [process=6][thread=MainThread] CheckpointManager init: checkpointers=None, item_names=('items',), item_handlers={'items': <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x79c6f4693bf0>}, handler_registry=None I0419 19:09:21.557178 133985913878336 composite_checkpoint_handler.py:237] Deferred registration for item: "items". Adding handler `<orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x79c6f4693bf0>` 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`. I0419 19:09:21.557226 133985913878336 composite_checkpoint_handler.py:237] Deferred registration for item: "metrics". Adding handler `<orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x79c6f46975c0>` 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`. I0419 19:09:21.557260 133985913878336 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 0x79c6f4693bf0>, ('items', <class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeRestoreArgs'>): <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x79c6f4693bf0>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonSaveArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x79c6f46975c0>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonRestoreArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x79c6f46975c0>}). I0419 19:09:21.557606 133985913878336 abstract_checkpointer.py:35] orbax-checkpoint version: 0.11.34 I0419 19:09:23.674398 133863594522368 checkpoint.py:228] Read Metadata={'item_handlers': {'items': 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler'}, 'metrics': {}, 'performance_metrics': {}, 'init_timestamp_nsecs': 1776625597738653940, 'commit_timestamp_nsecs': 1776625647386592342, 'custom_metadata': {}} from gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/9/_CHECKPOINT_METADATA I0419 19:09:23.920253 133863594522368 checkpoint_manager.py:1871] Missing metrics for step 9 I0419 19:09:24.744746 133985913878336 checkpoint_manager.py:1812] Found 3 checkpoint steps in gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints I0419 19:09:25.213349 133985913878336 checkpoint_manager.py:929] [process=6][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_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints: <orbax.checkpoint.checkpoint_manager.CheckpointManager object at 0x79c6f4692b40> I0419 19:09:25.213549 133985913878336 checkpointing.py:301] Checkpoint manager created! I0419 19:09:26.150120 133985913878336 nnx_wrappers.py:437] Unknown Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_norm_length', 'activation_embed'). I0419 19:09:26.150233 133985913878336 nnx_wrappers.py:437] Unknown Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None). I0419 19:09:26.527633 133985913878336 attentions.py:1088] attentions/inputs_q Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed'). I0419 19:09:26.527744 133985913878336 attentions.py:1088] attentions/inputs_q Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None). I0419 19:09:26.544821 133985913878336 attentions.py:1089] attentions/inputs_kv Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed'). I0419 19:09:26.544883 133985913878336 attentions.py:1089] attentions/inputs_kv Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None). I0419 19:09:26.569520 133985913878336 attentions.py:1154] attentions/query Logical: bfloat16[32,2048,16,128].................................... ('activation_kv_batch', 'activation_attn_length', 'activation_kv_heads', 'activation_kv_head_dim'). I0419 19:09:26.569588 133985913878336 attentions.py:1154] attentions/query Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0419 19:09:26.585970 133985913878336 attentions.py:1155] attentions/key Logical: bfloat16[32,2048,16,128].................................... ('activation_kv_batch', 'activation_attn_length', 'activation_kv_heads', 'activation_kv_head_dim'). I0419 19:09:26.586034 133985913878336 attentions.py:1155] attentions/key Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0419 19:09:26.602183 133985913878336 attentions.py:1156] attentions/value Logical: bfloat16[32,2048,16,128].................................... ('activation_kv_batch', 'activation_attn_length', 'activation_kv_heads', 'activation_kv_head_dim'). I0419 19:09:26.602242 133985913878336 attentions.py:1156] attentions/value Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0419 19:09:26.626636 133985913878336 attentions.py:1197] attentions/out Logical: bfloat16[32,2048,16,128].................................... ('activation_batch', 'activation_attn_length', 'activation_heads', 'activation_kv'). I0419 19:09:26.626701 133985913878336 attentions.py:1197] attentions/out Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None). I0419 19:09:26.647455 133985913878336 linears.py:525] linears/x Logical: bfloat16[32,2048,7168]...................................... ('activation_batch', 'activation_length', 'activation_mlp'). I0419 19:09:26.647516 133985913878336 linears.py:525] linears/x Physical: bfloat16[32,2048,7168]...................................... ('fsdp', None, None). I0419 19:09:26.862386 133985913878336 checkpointing.py:577] checkpoint manager exists so trying to load this run's existing checkpoint I0419 19:09:26.862512 133985913878336 checkpointing.py:581] restoring from this run's directory step 9 I0419 19:09:27.117032 133985913878336 event_tracking.py:70] [process=6] [sync] Started load checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/9. I0419 19:09:27.790103 133985913878336 checkpointer.py:307] Restoring checkpoint from gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/9. I0419 19:09:27.790565 133985913878336 event_tracking.py:125] [process=6] [sync] Finished blocking load in 0.67 seconds. Continuing load @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/9. I0419 19:09:30.042497 1464 google_auth_provider.cc:181] Running on GCE, using service account 562977990677-compute@developer.gserviceaccount.com I0419 19:09:36.222168 133985913878336 jax_array_handlers.py:843] [process=6] /jax/orbax/read/worker/io/requested throughput: 255.478 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 6.185547828674316 s) (per-host) I0419 19:09:36.226655 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/checkpoint/read/gbytes_per_sec: 240.449 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 6.581814765930176 s) (per-host) I0419 19:09:37.755293 133985913878336 event_tracking.py:138] [process=6] [sync] Finished load in 10.64 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/9 I0419 19:09:37.755483 133985913878336 standard_logger.py:34] {'step': 9, 'event_type': 'restore', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints', 'checkpointer_start_time': 1776625767.1169538, 'checkpointer_duration_secs': 10.63849663734436, 'checkpoint_manager_start_time': 1776625766.8627515, 'checkpoint_manager_duration_secs': 10.892701387405396} fsdp: 32 I0419 19:09:38.168085 133985913878336 maxtext_utils.py:1654] params/params/decoder/decoder_norm/scale Shape: float32[2048] Logical: P('norm',) Physical: (None,) I0419 19:09:38.168216 133985913878336 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) I0419 19:09:38.168269 133985913878336 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) I0419 19:09:38.168328 133985913878336 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') I0419 19:09:38.168380 133985913878336 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) I0419 19:09:38.168485 133985913878336 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) I0419 19:09:38.168553 133985913878336 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) I0419 19:09:38.168609 133985913878336 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') I0419 19:09:38.168651 133985913878336 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) I0419 19:09:38.168688 133985913878336 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) I0419 19:09:38.168735 133985913878336 maxtext_utils.py:1654] params/params/decoder/logits_dense/kernel Shape: float32[2048,32000] Logical: P('embed_vocab', 'vocab') Physical: ('fsdp', None) I0419 19:09:38.168781 133985913878336 maxtext_utils.py:1654] params/params/token_embedder/embedding Shape: float32[32000,2048] Logical: P('vocab', 'embed_vocab') Physical: (None, 'fsdp') I0419 19:09:38.651689 133985913878336 train.py:155] train/xent Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length'). I0419 19:09:38.651784 133985913878336 train.py:155] train/xent Physical: float32[32,2048]............................................ ('fsdp', None). I0419 19:09:38.667126 133985913878336 train.py:162] train/z_loss Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length'). I0419 19:09:38.667188 133985913878336 train.py:162] train/z_loss Physical: float32[32,2048]............................................ ('fsdp', None). I0419 19:09:49.275022 133985913878336 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. I0419 19:09:49.275830 133985913878336 metric_logger.py:301] number parameters: 1.104 billion I0419 19:10:00.372712 133985913878336 checkpointing.py:772] Waiting for step 10 to finish before checkpoint... I0419 19:10:01.069555 133985913878336 checkpointing.py:776] Waited 0.6968197822570801 seconds for step 10 to finish before starting checkpointing. I0419 19:10:01.071993 133985913878336 checkpoint_manager.py:2009] [process=6][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0419 19:10:01.074090 133985913878336 checkpoint_manager.py:1512] [process=6] Saving checkpoint at step 10 I0419 19:10:01.075567 133985913878336 event_tracking.py:70] [process=6] [sync] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/10. I0419 19:10:04.487335 133985913878336 signaling_client.py:364] Using JaxDistributedSignalingClient I0419 19:10:04.488744 133985913878336 future.py:372] [process=6][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. I0419 19:10:05.883333 133985913878336 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array. I0419 19:10:05.883443 133985913878336 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 I0419 19:10:06.165654 133985913878336 base_pytree_checkpoint_handler.py:154] [process=6][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.283403s I0419 19:10:06.165835 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/orbax/write/blocking_gbytes_per_sec: 5.362 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.2876894474029541 s) (per-host) I0419 19:10:06.165892 133985913878336 base_pytree_checkpoint_handler.py:768] [process=6][thread=MainThread] Initiated Pytree async_save. Time taken: 0.287756s (batch_requests_ready=0.002333s, total_serialization_initiated=0.285348s, others=0.000075s) I0419 19:10:06.166015 133985913878336 composite_checkpoint_handler.py:715] [process=6][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 1.678765s (all_items=0.000041s, per_item={'items': '0.00004148'}, temp_paths=1.678724) I0419 19:10:06.166077 133985913878336 future.py:372] [process=6][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. I0419 19:10:06.166131 133985913878336 future.py:372] [process=6][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. I0419 19:10:08.297186 133863560951552 array_metadata_store.py:203] [process=6][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/10/items/array_metadatas/process_6 I0419 19:10:44.525487 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/orbax/write/gbytes_per_sec: 40.872 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 38.647308349609375 s) (per-host) I0419 19:10:49.493204 133985913878336 event_tracking.py:125] [process=6] [sync] Finished blocking save in 48.42 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/10. I0419 19:10:54.413159 133985913878336 event_tracking.py:138] [process=6] [sync] Finished save in 53.34 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/10 I0419 19:10:54.415802 133985913878336 checkpoint_manager.py:2137] [process=6][thread=MainThread][step=10] CheckpointManager Save Finalize is syncing with other hosts... I0419 19:10:54.417209 133985913878336 checkpoint_manager.py:2146] [process=6][thread=MainThread][step=10] CheckpointManager Save Finalize is done on all hosts. I0419 19:10:54.417262 133985913878336 checkpoint_manager.py:1581] [process=6][thread=MainThread][step=10] Finished synchronous save. I0419 19:10:54.417320 133985913878336 standard_logger.py:34] {'step': 10, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': True, 'wait_for_prev_start_time': 1776625801.0719635, 'wait_for_prev_duration_secs': 6.985664367675781e-05, 'time_between_consecutive_saves_sec': None, 'checkpointer_blocking_start_time': 1776625801.0741317, 'checkpointer_blocking_duration_secs': 53.339144468307495, 'get_old_steps_start_time': 1776625854.4132962, 'get_old_steps_duration_secs': 2.9087066650390625e-05, 'checkpoint_manager_blocking_start_time': 1776625801.070113, 'checkpoint_manager_blocking_duration_secs': 53.34717559814453} I0419 19:10:54.417454 133985913878336 checkpointing.py:410] Saved a checkpoint at step 10. I0419 19:10:54.417524 133985913878336 max_utils.py:750] Memstats: After params initialized: I0419 19:10:54.417596 133985913878336 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_24(process=6,(0,6,0,0)) I0419 19:10:54.417669 133985913878336 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_25(process=6,(1,6,0,0)) I0419 19:10:54.417723 133985913878336 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_28(process=6,(0,7,0,0)) I0419 19:10:54.417767 133985913878336 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_29(process=6,(1,7,0,0)) I0419 19:10:54.731858 133985913878336 metric_logger.py:196] completed step: 10, seconds: 11.097, TFLOP/s/device: 1.224, Tokens/s/device: 184.558, total_weights: 65536, loss: 6.833, lm_loss: 6.833, perplexity: 927.869 I0419 19:10:54.899126 133985913878336 metric_logger.py:196] completed step: 11, seconds: 54.357, TFLOP/s/device: 0.250, Tokens/s/device: 37.677, total_weights: 65536, loss: 6.527, lm_loss: 6.527, perplexity: 683.659 I0419 19:10:55.046657 133985913878336 metric_logger.py:196] completed step: 12, seconds: 0.020, TFLOP/s/device: 673.263, Tokens/s/device: 101481.592, total_weights: 65536, loss: 6.265, lm_loss: 6.265, perplexity: 526.068 I0419 19:10:55.194326 133985913878336 metric_logger.py:196] completed step: 13, seconds: 0.154, TFLOP/s/device: 88.447, Tokens/s/device: 13331.684, total_weights: 65536, loss: 6.045, lm_loss: 6.045, perplexity: 422.001 I0419 19:10:55.199127 133985913878336 checkpointing.py:772] Waiting for step 15 to finish before checkpoint... I0419 19:10:55.488557 133985913878336 checkpointing.py:776] Waited 0.28939199447631836 seconds for step 15 to finish before starting checkpointing. I0419 19:10:55.491482 133985913878336 checkpoint_manager.py:2009] [process=6][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0419 19:10:55.492970 133985913878336 checkpoint_manager.py:1512] [process=6] Saving checkpoint at step 15 I0419 19:10:55.494917 133985913878336 event_tracking.py:70] [process=6] [sync] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/15. I0419 19:10:59.315656 133985913878336 future.py:372] [process=6][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. I0419 19:11:01.124821 133985913878336 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array. I0419 19:11:01.124920 133985913878336 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 I0419 19:11:01.152332 133985913878336 base_pytree_checkpoint_handler.py:154] [process=6][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.028777s I0419 19:11:01.152532 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/orbax/write/blocking_gbytes_per_sec: 47.229 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.03266143798828125 s) (per-host) I0419 19:11:01.152591 133985913878336 base_pytree_checkpoint_handler.py:768] [process=6][thread=MainThread] Initiated Pytree async_save. Time taken: 0.032732s (batch_requests_ready=0.001810s, total_serialization_initiated=0.030845s, others=0.000077s) I0419 19:11:01.159641 133985913878336 composite_checkpoint_handler.py:715] [process=6][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 1.845289s (all_items=0.000023s, per_item={'items': '0.00002337'}, temp_paths=1.845265) I0419 19:11:01.159708 133985913878336 future.py:372] [process=6][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. I0419 19:11:01.159751 133985913878336 future.py:372] [process=6][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. I0419 19:11:03.642683 133863560951552 array_metadata_store.py:203] [process=6][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/15/items/array_metadatas/process_6 I0419 19:11:40.188883 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/orbax/write/gbytes_per_sec: 40.431 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 39.0689754486084 s) (per-host) I0419 19:11:46.262994 133985913878336 event_tracking.py:125] [process=6] [sync] Finished blocking save in 50.77 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/15. I0419 19:11:50.984342 133985913878336 event_tracking.py:138] [process=6] [sync] Finished save in 55.49 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/15 I0419 19:11:50.987236 133985913878336 checkpoint_manager.py:2137] [process=6][thread=MainThread][step=15] CheckpointManager Save Finalize is syncing with other hosts... I0419 19:11:50.988737 133985913878336 checkpoint_manager.py:2146] [process=6][thread=MainThread][step=15] CheckpointManager Save Finalize is done on all hosts. I0419 19:11:50.988788 133985913878336 checkpoint_manager.py:1581] [process=6][thread=MainThread][step=15] Finished synchronous save. I0419 19:11:50.988839 133985913878336 standard_logger.py:34] {'step': 15, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': True, 'wait_for_prev_start_time': 1776625855.49146, 'wait_for_prev_duration_secs': 6.127357482910156e-05, 'time_between_consecutive_saves_sec': 1.0742087364196777, 'checkpointer_blocking_start_time': 1776625855.4930093, 'checkpointer_blocking_duration_secs': 55.49149203300476, 'get_old_steps_start_time': 1776625910.9845207, 'get_old_steps_duration_secs': 2.8848648071289062e-05, 'checkpoint_manager_blocking_start_time': 1776625855.4892416, 'checkpoint_manager_blocking_duration_secs': 55.49957323074341} I0419 19:11:50.988927 133985913878336 checkpointing.py:410] Saved a checkpoint at step 15. I0419 19:11:50.989716 133985913878336 metric_logger.py:196] completed step: 14, seconds: 0.147, TFLOP/s/device: 92.172, Tokens/s/device: 13893.223, total_weights: 65536, loss: 5.864, lm_loss: 5.864, perplexity: 352.193 I0419 19:11:50.995699 133985913878336 metric_logger.py:196] completed step: 15, seconds: 0.148, TFLOP/s/device: 92.014, Tokens/s/device: 13869.325, total_weights: 65536, loss: 5.719, lm_loss: 5.719, perplexity: 304.661 I0419 19:12:12.270371 133985913878336 metric_logger.py:196] completed step: 16, seconds: 55.795, TFLOP/s/device: 0.244, Tokens/s/device: 36.706, total_weights: 65536, loss: 5.605, lm_loss: 5.605, perplexity: 271.872 I0419 19:12:12.418157 133985913878336 metric_logger.py:196] completed step: 17, seconds: 21.129, TFLOP/s/device: 0.643, Tokens/s/device: 96.930, total_weights: 65536, loss: 5.517, lm_loss: 5.517, perplexity: 248.975 I0419 19:12:12.565638 133985913878336 metric_logger.py:196] completed step: 18, seconds: 0.152, TFLOP/s/device: 89.310, Tokens/s/device: 13461.817, total_weights: 65536, loss: 5.448, lm_loss: 5.448, perplexity: 232.333 I0419 19:12:12.712734 133985913878336 checkpointing.py:772] Waiting for step 19 to finish before checkpoint... I0419 19:12:12.713351 133985913878336 checkpointing.py:776] Waited 0.0006363391876220703 seconds for step 19 to finish before starting checkpointing. I0419 19:12:12.715577 133985913878336 checkpoint_manager.py:2009] [process=6][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0419 19:12:12.717510 133985913878336 checkpoint_manager.py:1512] [process=6] Saving checkpoint at step 19 I0419 19:12:12.718924 133985913878336 event_tracking.py:70] [process=6] [sync] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/19. I0419 19:12:16.577964 133985913878336 future.py:372] [process=6][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. I0419 19:12:18.004152 133985913878336 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array. I0419 19:12:18.004246 133985913878336 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 I0419 19:12:18.031920 133985913878336 base_pytree_checkpoint_handler.py:154] [process=6][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.028975s I0419 19:12:18.032084 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/orbax/write/blocking_gbytes_per_sec: 47.303 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.03261065483093262 s) (per-host) I0419 19:12:18.038438 133985913878336 base_pytree_checkpoint_handler.py:768] [process=6][thread=MainThread] Initiated Pytree async_save. Time taken: 0.038949s (batch_requests_ready=0.001753s, total_serialization_initiated=0.030852s, others=0.006344s) I0419 19:12:18.038711 133985913878336 composite_checkpoint_handler.py:715] [process=6][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 1.461888s (all_items=0.000026s, per_item={'items': '0.00002646'}, temp_paths=1.461861) I0419 19:12:18.038762 133985913878336 future.py:372] [process=6][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. I0419 19:12:18.038803 133985913878336 future.py:372] [process=6][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. I0419 19:12:21.017335 133863560951552 array_metadata_store.py:203] [process=6][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/19/items/array_metadatas/process_6 I0419 19:12:56.425139 133985913878336 base_pytree_checkpoint_handler.py:130] [process=6] /jax/orbax/write/gbytes_per_sec: 41.108 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 38.42563438415527 s) (per-host) I0419 19:13:02.971192 133985913878336 event_tracking.py:125] [process=6] [sync] Finished blocking save in 50.25 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/19. I0419 19:13:07.687499 133985913878336 event_tracking.py:138] [process=6] [sync] Finished save in 54.97 seconds @ gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints/19 I0419 19:13:07.689373 133985913878336 checkpoint_manager.py:2137] [process=6][thread=MainThread][step=19] CheckpointManager Save Finalize is syncing with other hosts... I0419 19:13:07.691280 133985913878336 checkpoint_manager.py:2146] [process=6][thread=MainThread][step=19] CheckpointManager Save Finalize is done on all hosts. I0419 19:13:07.691332 133985913878336 checkpoint_manager.py:1581] [process=6][thread=MainThread][step=19] Finished synchronous save. I0419 19:13:07.691388 133985913878336 standard_logger.py:34] {'step': 19, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260419_180002/linen_xpk_main_20260419_180002_14_async_ckpt_false/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': True, 'wait_for_prev_start_time': 1776625932.7155583, 'wait_for_prev_duration_secs': 5.698204040527344e-05, 'time_between_consecutive_saves_sec': 21.726781606674194, 'checkpointer_blocking_start_time': 1776625932.7175462, 'checkpointer_blocking_duration_secs': 54.97006583213806, 'get_old_steps_start_time': 1776625987.6876261, 'get_old_steps_duration_secs': 2.1457672119140625e-05, 'checkpoint_manager_blocking_start_time': 1776625932.7135932, 'checkpoint_manager_blocking_duration_secs': 54.97776532173157} I0419 19:13:07.691482 133985913878336 checkpointing.py:410] Saved a checkpoint at step 19. I0419 19:13:07.691516 133985913878336 checkpoint_manager.py:2009] [process=6][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0419 19:13:07.691546 133985913878336 checkpoint_manager.py:2009] [process=6][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning. I0419 19:13:07.692133 133985913878336 metric_logger.py:196] completed step: 19, seconds: 0.148, TFLOP/s/device: 91.733, Tokens/s/device: 13827.000, total_weights: 65536, loss: 5.391, lm_loss: 5.391, perplexity: 219.349 Per train step: Total TFLOPs: 13.59 split as 93.93% learnable weight flops and 6.07% attention flops XPK End: Sun Apr 19 19:13:18 UTC 2026 EXIT_CODE=0