XPK Start: Sat Apr 18 19:40:31 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 19:40:54.819016: 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 19:40:55.358118 133840646793024 max_utils.py:273] Attempting to initialize the jax distributed system...
I0418 19:41:04.398563 133840646793024 distributed.py:149] Starting JAX distributed service on [::]:8482
I0418 19:41:04.401195 133840646793024 distributed.py:172] Connecting to JAX distributed service on mt-16-zarr3-true-sv-k8ltr-slice-job-0-0.mt-16-zarr3-true-sv-k8ltr:8482
I0418 19:41:05.909374 133840646793024 max_utils.py:284] Jax distributed system initialized!
I0418 19:41:12.337016 133840646793024 max_utils.py:800] System Information: Jax Version: 0.9.2
I0418 19:41:12.337119 133840646793024 max_utils.py:801] System Information: Jaxlib Version: 0.9.2
I0418 19:41:12.337160 133840646793024 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 19:41:12.337193 133840646793024 train_utils.py:348] WARNING: Sequence packing is essentially ignored for synthetic data. Please use a real dataset to use sequence packing.
I0418 19:41:13.030496 133840646793024 maxtext_utils.py:1551] Num_devices: 32, shape (1, 1, 1, 32, 1, 1, 1, 1, 1, 1, 1, 1, 1)
I0418 19:41:13.030770 133840646793024 checkpointing.py:677] Setting up checkpoint logger...
I0418 19:41:13.030822 133840646793024 checkpointing.py:233] Creating checkpoint manager with ocdbt=True and zarr3=True
I0418 19:41:13.030867 133840646793024 pytree_checkpoint_handler.py:592] save_device_host_concurrent_bytes=None
I0418 19:41:13.031199 133840646793024 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 0x79b993b140e0>, enable_pinned_host_transfer=False, save_concurrent_bytes: 96000000000 (89.4 GiB), restore_concurrent_bytes: 96000000000 (89.4 GiB)
I0418 19:41:16.286580 133840646793024 checkpointing.py:265] Enabling policy for fixed interval checkpointing.
I0418 19:41:16.286815 133840646793024 checkpoint_manager.py:708] [process=5][thread=MainThread] CheckpointManager init: checkpointers=None, item_names=('items',), item_handlers={'items': <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x79a52069bd10>}, handler_registry=None
I0418 19:41:16.287057 133840646793024 composite_checkpoint_handler.py:237] Deferred registration for item: "items". Adding handler `<orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x79a52069bd10>` 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 19:41:16.287107 133840646793024 composite_checkpoint_handler.py:237] Deferred registration for item: "metrics". Adding handler `<orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x79a52069d7f0>` 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 19:41:16.287144 133840646793024 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 0x79a52069bd10>, ('items', <class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeRestoreArgs'>): <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x79a52069bd10>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonSaveArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x79a52069d7f0>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonRestoreArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x79a52069d7f0>}).
I0418 19:41:16.287483 133840646793024 abstract_checkpointer.py:35] orbax-checkpoint version: 0.11.34
I0418 19:41:16.287556 133840646793024 async_checkpointer.py:192] [process=5][thread=MainThread] Using barrier_sync_fn: <function get_barrier_sync_fn.<locals>._fn at 0x79a5202d3880> timeout: 1200 secs and primary_host=0 for async checkpoint writes
I0418 19:41:17.830642 133840646793024 checkpoint_manager.py:1812] Found 0 checkpoint steps in gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints
I0418 19:41:17.877970 133840646793024 checkpoint_manager.py:929] [process=5][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=True, 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_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints: <orbax.checkpoint.checkpoint_manager.CheckpointManager object at 0x79a52069ae70>
I0418 19:41:17.878124 133840646793024 checkpointing.py:301] Checkpoint manager created!
I0418 19:41:18.798441 133840646793024 nnx_wrappers.py:437] Unknown Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_norm_length', 'activation_embed').
I0418 19:41:18.798566 133840646793024 nnx_wrappers.py:437] Unknown Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None).
I0418 19:41:19.174302 133840646793024 attentions.py:1088] attentions/inputs_q Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed').
I0418 19:41:19.174396 133840646793024 attentions.py:1088] attentions/inputs_q Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None).
I0418 19:41:19.190680 133840646793024 attentions.py:1089] attentions/inputs_kv Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed').
I0418 19:41:19.190748 133840646793024 attentions.py:1089] attentions/inputs_kv Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None).
I0418 19:41:19.215103 133840646793024 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 19:41:19.215173 133840646793024 attentions.py:1154] attentions/query Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 19:41:19.231564 133840646793024 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 19:41:19.231621 133840646793024 attentions.py:1155] attentions/key Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 19:41:19.247776 133840646793024 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 19:41:19.247834 133840646793024 attentions.py:1156] attentions/value Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 19:41:19.272228 133840646793024 attentions.py:1197] attentions/out Logical: bfloat16[32,2048,16,128].................................... ('activation_batch', 'activation_attn_length', 'activation_heads', 'activation_kv').
I0418 19:41:19.272297 133840646793024 attentions.py:1197] attentions/out Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 19:41:19.293247 133840646793024 linears.py:525] linears/x Logical: bfloat16[32,2048,7168]...................................... ('activation_batch', 'activation_length', 'activation_mlp').
I0418 19:41:19.293314 133840646793024 linears.py:525] linears/x Physical: bfloat16[32,2048,7168]...................................... ('fsdp', None, None).
I0418 19:41:19.507429 133840646793024 checkpointing.py:577] checkpoint manager exists so trying to load this run's existing checkpoint
I0418 19:41:19.507579 133840646793024 checkpointing.py:665] No existing checkpoints found, not restoring checkpoint.
fsdp: 32
I0418 19:41:20.926434 133840646793024 maxtext_utils.py:1654] params/params/decoder/decoder_norm/scale
Shape: float32[2048]
Logical: P('norm',)
Physical: (None,)
I0418 19:41:20.926605 133840646793024 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 19:41:20.926656 133840646793024 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 19:41:20.926715 133840646793024 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 19:41:20.926769 133840646793024 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 19:41:20.926807 133840646793024 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 19:41:20.926859 133840646793024 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 19:41:20.926912 133840646793024 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 19:41:20.926949 133840646793024 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 19:41:20.926991 133840646793024 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 19:41:20.927035 133840646793024 maxtext_utils.py:1654] params/params/decoder/logits_dense/kernel
Shape: float32[2048,32000]
Logical: P('embed_vocab', 'vocab')
Physical: ('fsdp', None)
I0418 19:41:20.927083 133840646793024 maxtext_utils.py:1654] params/params/token_embedder/embedding
Shape: float32[32000,2048]
Logical: P('vocab', 'embed_vocab')
Physical: (None, 'fsdp')
I0418 19:41:21.414688 133840646793024 train.py:155] train/xent Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length').
I0418 19:41:21.414781 133840646793024 train.py:155] train/xent Physical: float32[32,2048]............................................ ('fsdp', None).
I0418 19:41:21.429993 133840646793024 train.py:162] train/z_loss Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length').
I0418 19:41:21.430052 133840646793024 train.py:162] train/z_loss Physical: float32[32,2048]............................................ ('fsdp', None).
I0418 19:41:32.417014 133840646793024 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 19:41:32.417875 133840646793024 metric_logger.py:301] number parameters: 1.104 billion
I0418 19:41:43.974220 133840646793024 checkpointing.py:772] Waiting for step 0 to finish before checkpoint...
I0418 19:41:44.127358 133840646793024 checkpointing.py:776] Waited 0.15311574935913086 seconds for step 0 to finish before starting checkpointing.
I0418 19:41:44.130074 133840646793024 checkpoint_manager.py:2009] [process=5][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning.
I0418 19:41:44.131706 133840646793024 checkpoint_manager.py:1512] [process=5] Saving checkpoint at step 0
I0418 19:41:44.133169 133840646793024 event_tracking.py:70] [process=5] [async] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/0.
I0418 19:41:44.893867 133840646793024 signaling_client.py:364] Using JaxDistributedSignalingClient
I0418 19:41:44.894841 133840646793024 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array.
I0418 19:41:44.894897 133840646793024 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 19:41:45.166440 133840646793024 base_pytree_checkpoint_handler.py:154] [process=5][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.272650s
I0418 19:41:45.166614 133840646793024 base_pytree_checkpoint_handler.py:130] [process=5] /jax/orbax/write/blocking_gbytes_per_sec: 5.545 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.2781999111175537 s) (per-host)
I0418 19:41:45.166666 133840646793024 base_pytree_checkpoint_handler.py:768] [process=5][thread=MainThread] Initiated Pytree async_save. Time taken: 0.278263s (batch_requests_ready=0.002319s, total_serialization_initiated=0.275873s, others=0.000071s)
I0418 19:41:45.166760 133840646793024 composite_checkpoint_handler.py:715] [process=5][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 0.282609s (all_items=0.000017s, per_item={'items': '0.00001717'}, temp_paths=0.282592)
I0418 19:41:45.167543 133840646793024 event_tracking.py:125] [process=5] [async] Finished blocking save in 1.04 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/0.
I0418 19:41:45.167850 133711766771456 async_checkpointer.py:76] [process=5][thread=async_save] Background save thread started. Deadline for this save operation is 2026-04-18 20:01:45.167815
I0418 19:41:45.178604 133840646793024 checkpoint_manager.py:1560] [process=5][thread=MainThread][step=0] Starting CheckpointManager Save Finalize thread=save_finalize
I0418 19:41:45.178866 133710134810368 async_checkpointer.py:280] [process=5][thread=save_finalize] Waiting for background save thread=async_save.
I0418 19:41:45.179003 133840646793024 standard_logger.py:34] {'step': 0, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': False, 'wait_for_prev_start_time': 1776541304.1300542, 'wait_for_prev_duration_secs': 6.914138793945312e-05, 'time_between_consecutive_saves_sec': None, 'checkpointer_blocking_start_time': 1776541304.1317475, 'checkpointer_blocking_duration_secs': 1.0362529754638672, 'get_old_steps_start_time': 1776541305.1680255, 'get_old_steps_duration_secs': 3.170967102050781e-05, 'checkpoint_manager_blocking_start_time': 1776541304.1278975, 'checkpoint_manager_blocking_duration_secs': 1.0510647296905518}
I0418 19:41:45.179117 133840646793024 checkpointing.py:408] Started an asynchronous checkpoint save for step 0
I0418 19:41:45.179167 133840646793024 max_utils.py:750]
Memstats: After params initialized:
I0418 19:41:45.179217 133840646793024 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_18(process=5,(2,4,0,0))
I0418 19:41:45.179250 133840646793024 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_19(process=5,(3,4,0,0))
I0418 19:41:45.179276 133840646793024 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_22(process=5,(2,5,0,0))
I0418 19:41:45.179308 133840646793024 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_23(process=5,(3,5,0,0))
I0418 19:41:45.494714 133840646793024 metric_logger.py:196] completed step: 0, seconds: 11.556, TFLOP/s/device: 1.176, Tokens/s/device: 177.221, total_weights: 65536, loss: 10.874, lm_loss: 10.874, perplexity: 52779.875
I0418 19:41:45.664395 133840646793024 metric_logger.py:196] completed step: 1, seconds: 1.519, TFLOP/s/device: 8.945, Tokens/s/device: 1348.256, total_weights: 65536, loss: 10.874, lm_loss: 10.874, perplexity: 52779.875
I0418 19:41:46.047515 133840646793024 metric_logger.py:196] completed step: 2, seconds: 0.022, TFLOP/s/device: 607.572, Tokens/s/device: 91579.842, total_weights: 65536, loss: 10.560, lm_loss: 10.560, perplexity: 38547.719
I0418 19:41:46.194944 133840646793024 metric_logger.py:196] completed step: 3, seconds: 0.383, TFLOP/s/device: 35.467, Tokens/s/device: 5346.002, total_weights: 65536, loss: 9.980, lm_loss: 9.980, perplexity: 21590.506
I0418 19:41:46.199642 133840646793024 checkpointing.py:772] Waiting for step 5 to finish before checkpoint...
I0418 19:41:46.488964 133840646793024 checkpointing.py:776] Waited 0.2892897129058838 seconds for step 5 to finish before starting checkpointing.
I0418 19:41:46.491967 133840646793024 checkpoint_manager.py:2020] [process=5][thread=MainThread][step=0][wait_until_finished] Waiting for Save Finalize thread (save_finalize) to complete.
I0418 19:41:53.559629 2838 google_auth_provider.cc:181] Running on GCE, using service account 562977990677-compute@developer.gserviceaccount.com
I0418 19:41:55.615010 133710143203072 array_metadata_store.py:203] [process=5][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/0/items/array_metadatas/process_5
I0418 19:42:27.619488 133711766771456 base_pytree_checkpoint_handler.py:130] [process=5] /jax/orbax/write/gbytes_per_sec: 36.966 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 42.731032609939575 s) (per-host)
I0418 19:42:27.619601 133711766771456 async_checkpointer.py:90] [process=5][thread=async_save] 3 Handler Commit operations completed. Time taken: 42.451644s.
I0418 19:42:36.183617 133711766771456 async_checkpointer.py:160] [process=5][thread=async_save] Background save thread done. Time taken: 51.015644s.
I0418 19:42:36.183895 133710134810368 async_checkpointer.py:288] [process=5][thread=save_finalize] Done with waiting for background save thread=async_save.
I0418 19:42:36.184018 133710134810368 async_checkpointer.py:298] [process=5][thread=save_finalize] No errors found in background save thread=async_save.
I0418 19:42:36.184069 133710134810368 checkpoint_manager.py:2137] [process=5][thread=save_finalize][step=0] CheckpointManager Save Finalize is syncing with other hosts...
I0418 19:42:36.187174 133710134810368 checkpoint_manager.py:2146] [process=5][thread=save_finalize][step=0] CheckpointManager Save Finalize is done on all hosts.
I0418 19:42:36.187361 133840646793024 checkpoint_manager.py:2032] [process=5][thread=MainThread][step=0][wait_until_finished] Done waiting for Save Finalize thread (save_finalize) running at step=0.
W0418 19:42:36.187518 133840646793024 checkpoint_manager.py:1452] Waiting for previous save to complete took 49.695550 seconds. If this number is high, consider checkpointing less frequently.
I0418 19:42:36.189364 133840646793024 checkpoint_manager.py:1512] [process=5] Saving checkpoint at step 5
I0418 19:42:36.191747 133840646793024 event_tracking.py:70] [process=5] [async] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/5.
I0418 19:42:36.921232 133840646793024 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array.
I0418 19:42:36.921328 133840646793024 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 19:42:36.954641 133840646793024 base_pytree_checkpoint_handler.py:154] [process=5][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.034478s
I0418 19:42:36.954806 133840646793024 base_pytree_checkpoint_handler.py:130] [process=5] /jax/orbax/write/blocking_gbytes_per_sec: 40.614 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.03798174858093262 s) (per-host)
I0418 19:42:36.954857 133840646793024 base_pytree_checkpoint_handler.py:768] [process=5][thread=MainThread] Initiated Pytree async_save. Time taken: 0.038041s (batch_requests_ready=0.001878s, total_serialization_initiated=0.036098s, others=0.000066s)
I0418 19:42:36.954945 133840646793024 composite_checkpoint_handler.py:715] [process=5][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 0.043204s (all_items=0.000015s, per_item={'items': '0.00001550'}, temp_paths=0.043189)
I0418 19:42:36.955520 133840646793024 event_tracking.py:125] [process=5] [async] Finished blocking save in 0.77 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/5.
I0418 19:42:36.955807 133689463772928 async_checkpointer.py:76] [process=5][thread=async_save] Background save thread started. Deadline for this save operation is 2026-04-18 20:02:36.955770
I0418 19:42:36.964551 133840646793024 checkpoint_manager.py:1560] [process=5][thread=MainThread][step=5] Starting CheckpointManager Save Finalize thread=save_finalize
I0418 19:42:36.964816 133710134810368 async_checkpointer.py:280] [process=5][thread=save_finalize] Waiting for background save thread=async_save.
I0418 19:42:36.964977 133840646793024 standard_logger.py:34] {'step': 5, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': False, 'wait_for_prev_start_time': 1776541306.4919386, 'wait_for_prev_duration_secs': 49.695550203323364, 'time_between_consecutive_saves_sec': None, 'checkpointer_blocking_start_time': 1776541356.1894033, 'checkpointer_blocking_duration_secs': 0.766512393951416, 'get_old_steps_start_time': 1776541356.9559362, 'get_old_steps_duration_secs': 2.5510787963867188e-05, 'checkpoint_manager_blocking_start_time': 1776541306.4896312, 'checkpoint_manager_blocking_duration_secs': 50.475311040878296}
I0418 19:42:36.965082 133840646793024 checkpointing.py:408] Started an asynchronous checkpoint save for step 5
I0418 19:42:36.965886 133840646793024 metric_logger.py:196] completed step: 4, seconds: 0.154, TFLOP/s/device: 88.488, Tokens/s/device: 13337.849, total_weights: 65536, loss: 9.460, lm_loss: 9.460, perplexity: 12840.355
I0418 19:42:36.971978 133840646793024 metric_logger.py:196] completed step: 5, seconds: 0.147, TFLOP/s/device: 92.227, Tokens/s/device: 13901.427, total_weights: 65536, loss: 8.959, lm_loss: 8.959, perplexity: 7776.467
I0418 19:42:43.338792 133710143203072 array_metadata_store.py:203] [process=5][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/5/items/array_metadatas/process_5
I0418 19:42:59.281384 133840646793024 metric_logger.py:196] completed step: 6, seconds: 50.771, TFLOP/s/device: 0.268, Tokens/s/device: 40.338, total_weights: 65536, loss: 8.469, lm_loss: 8.469, perplexity: 4762.740
I0418 19:42:59.428873 133840646793024 metric_logger.py:196] completed step: 7, seconds: 22.163, TFLOP/s/device: 0.613, Tokens/s/device: 92.405, total_weights: 65536, loss: 8.003, lm_loss: 8.003, perplexity: 2989.151
I0418 19:42:59.576227 133840646793024 metric_logger.py:196] completed step: 8, seconds: 0.152, TFLOP/s/device: 89.190, Tokens/s/device: 13443.613, total_weights: 65536, loss: 7.572, lm_loss: 7.572, perplexity: 1943.098
I0418 19:42:59.723091 133840646793024 checkpointing.py:772] Waiting for step 9 to finish before checkpoint...
I0418 19:42:59.723869 133840646793024 checkpointing.py:776] Waited 0.0007994174957275391 seconds for step 9 to finish before starting checkpointing.
I0418 19:42:59.725897 133840646793024 checkpoint_manager.py:2020] [process=5][thread=MainThread][step=5][wait_until_finished] Waiting for Save Finalize thread (save_finalize) to complete.
I0418 19:43:19.857069 133689463772928 base_pytree_checkpoint_handler.py:130] [process=5] /jax/orbax/write/gbytes_per_sec: 36.786 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 42.9402060508728 s) (per-host)
I0418 19:43:19.857176 133689463772928 async_checkpointer.py:90] [process=5][thread=async_save] 3 Handler Commit operations completed. Time taken: 42.900815s.
I0418 19:43:28.432404 133689463772928 async_checkpointer.py:160] [process=5][thread=async_save] Background save thread done. Time taken: 51.476027s.
I0418 19:43:28.432683 133710134810368 async_checkpointer.py:288] [process=5][thread=save_finalize] Done with waiting for background save thread=async_save.
I0418 19:43:28.432803 133710134810368 async_checkpointer.py:298] [process=5][thread=save_finalize] No errors found in background save thread=async_save.
I0418 19:43:28.432851 133710134810368 checkpoint_manager.py:2137] [process=5][thread=save_finalize][step=5] CheckpointManager Save Finalize is syncing with other hosts...
I0418 19:43:28.434412 133710134810368 checkpoint_manager.py:2146] [process=5][thread=save_finalize][step=5] CheckpointManager Save Finalize is done on all hosts.
I0418 19:43:28.434615 133840646793024 checkpoint_manager.py:2032] [process=5][thread=MainThread][step=5][wait_until_finished] Done waiting for Save Finalize thread (save_finalize) running at step=5.
W0418 19:43:28.434745 133840646793024 checkpoint_manager.py:1452] Waiting for previous save to complete took 28.708856 seconds. If this number is high, consider checkpointing less frequently.
I0418 19:43:28.436439 133840646793024 checkpoint_manager.py:1512] [process=5] Saving checkpoint at step 9
I0418 19:43:28.438435 133840646793024 event_tracking.py:70] [process=5] [async] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/9.
I0418 19:43:29.139147 133840646793024 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array.
I0418 19:43:29.139243 133840646793024 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 19:43:29.171083 133840646793024 base_pytree_checkpoint_handler.py:154] [process=5][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.032752s
I0418 19:43:29.171253 133840646793024 base_pytree_checkpoint_handler.py:130] [process=5] /jax/orbax/write/blocking_gbytes_per_sec: 42.501 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.03629469871520996 s) (per-host)
I0418 19:43:29.171303 133840646793024 base_pytree_checkpoint_handler.py:768] [process=5][thread=MainThread] Initiated Pytree async_save. Time taken: 0.036355s (batch_requests_ready=0.001771s, total_serialization_initiated=0.034519s, others=0.000065s)
I0418 19:43:29.171393 133840646793024 composite_checkpoint_handler.py:715] [process=5][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 0.040448s (all_items=0.000010s, per_item={'items': '0.00001025'}, temp_paths=0.040437)
I0418 19:43:29.172065 133840646793024 event_tracking.py:125] [process=5] [async] Finished blocking save in 0.74 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/9.
I0418 19:43:29.172330 133710134810368 async_checkpointer.py:76] [process=5][thread=async_save] Background save thread started. Deadline for this save operation is 2026-04-18 20:03:29.172305
I0418 19:43:29.176246 133840646793024 checkpoint_manager.py:1560] [process=5][thread=MainThread][step=9] Starting CheckpointManager Save Finalize thread=save_finalize
I0418 19:43:29.176495 133710720530176 async_checkpointer.py:280] [process=5][thread=save_finalize] Waiting for background save thread=async_save.
I0418 19:43:29.176640 133840646793024 standard_logger.py:34] {'step': 9, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': False, 'wait_for_prev_start_time': 1776541379.7258663, 'wait_for_prev_duration_secs': 28.708855628967285, 'time_between_consecutive_saves_sec': 23.53865146636963, 'checkpointer_blocking_start_time': 1776541408.4364924, 'checkpointer_blocking_duration_secs': 0.7359409332275391, 'get_old_steps_start_time': 1776541409.1724508, 'get_old_steps_duration_secs': 3.5762786865234375e-05, 'checkpoint_manager_blocking_start_time': 1776541379.724125, 'checkpoint_manager_blocking_duration_secs': 29.452481269836426}
I0418 19:43:29.176743 133840646793024 checkpointing.py:408] Started an asynchronous checkpoint save for step 9
I0418 19:43:29.176785 133840646793024 checkpoint_manager.py:2020] [process=5][thread=MainThread][step=9][wait_until_finished] Waiting for Save Finalize thread (save_finalize) to complete.
I0418 19:43:34.164968 133710143203072 array_metadata_store.py:203] [process=5][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260418_180002/linen_xpk_main_20260418_180002_16_zarr3_true/checkpoints/9/items/array_metadatas/process_5
I0418 19:44:11.084803 133710134810368 base_pytree_checkpoint_handler.py:130] [process=5] /jax/orbax/write/gbytes_per_sec: 37.654 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 41.94980573654175 s) (per-host)
I0418 19:44:11.084921 133710134810368 async_checkpointer.py:90] [process=5][thread=async_save] 3 Handler Commit operations completed. Time taken: 41.912513s.
I0418 19:44:19.574669 133710134810368 async_checkpointer.py:160] [process=5][thread=async_save] Background save thread done. Time taken: 50.402244s.
I0418 19:44:19.574945 133710720530176 async_checkpointer.py:288] [process=5][thread=save_finalize] Done with waiting for background save thread=async_save.
I0418 19:44:19.575069 133710720530176 async_checkpointer.py:298] [process=5][thread=save_finalize] No errors found in background save thread=async_save.
I0418 19:44:19.575111 133710720530176 checkpoint_manager.py:2137] [process=5][thread=save_finalize][step=9] CheckpointManager Save Finalize is syncing with other hosts...
I0418 19:44:19.576806 133710720530176 checkpoint_manager.py:2146] [process=5][thread=save_finalize][step=9] CheckpointManager Save Finalize is done on all hosts.
I0418 19:44:19.576997 133840646793024 checkpoint_manager.py:2032] [process=5][thread=MainThread][step=9][wait_until_finished] Done waiting for Save Finalize thread (save_finalize) running at step=9.
I0418 19:44:19.577149 133840646793024 checkpoint_manager.py:2009] [process=5][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning.
I0418 19:44:19.578088 133840646793024 metric_logger.py:196] completed step: 9, seconds: 0.147, TFLOP/s/device: 92.178, Tokens/s/device: 13894.071, 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 19:44:31 UTC 2026
EXIT_CODE=0