XPK Start: Sat Apr 18 00:04:43 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 00:05:08.699021: 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 00:05:09.233546 134760609109824 max_utils.py:273] Attempting to initialize the jax distributed system...
I0418 00:05:18.274761 134760609109824 distributed.py:149] Starting JAX distributed service on [::]:8482
I0418 00:05:18.277187 134760609109824 distributed.py:172] Connecting to JAX distributed service on mt-02-synthetic-jsi18-slice-job-0-0.mt-02-synthetic-jsi18:8482
I0418 00:05:19.871809 134760609109824 max_utils.py:284] Jax distributed system initialized!
I0418 00:05:26.016683 134760609109824 max_utils.py:800] System Information: Jax Version: 0.9.2
I0418 00:05:26.016785 134760609109824 max_utils.py:801] System Information: Jaxlib Version: 0.9.2
I0418 00:05:26.016824 134760609109824 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 00:05:26.016858 134760609109824 train_utils.py:348] WARNING: Sequence packing is essentially ignored for synthetic data. Please use a real dataset to use sequence packing.
I0418 00:05:26.708018 134760609109824 maxtext_utils.py:1551] Num_devices: 32, shape (1, 1, 1, 32, 1, 1, 1, 1, 1, 1, 1, 1, 1)
I0418 00:05:26.708298 134760609109824 checkpointing.py:677] Setting up checkpoint logger...
I0418 00:05:26.708350 134760609109824 checkpointing.py:233] Creating checkpoint manager with ocdbt=True and zarr3=True
I0418 00:05:26.708395 134760609109824 pytree_checkpoint_handler.py:592] save_device_host_concurrent_bytes=None
I0418 00:05:26.708805 134760609109824 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 0x7a8fcfb1b4d0>, enable_pinned_host_transfer=False, save_concurrent_bytes: 96000000000 (89.4 GiB), restore_concurrent_bytes: 96000000000 (89.4 GiB)
I0418 00:05:30.410940 134760609109824 checkpointing.py:265] Enabling policy for fixed interval checkpointing.
I0418 00:05:30.411177 134760609109824 checkpoint_manager.py:708] [process=1][thread=MainThread] CheckpointManager init: checkpointers=None, item_names=('items',), item_handlers={'items': <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7a7ba02d5b50>}, handler_registry=None
I0418 00:05:30.411437 134760609109824 composite_checkpoint_handler.py:237] Deferred registration for item: "items". Adding handler `<orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7a7ba02d5b50>` 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 00:05:30.411498 134760609109824 composite_checkpoint_handler.py:237] Deferred registration for item: "metrics". Adding handler `<orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x7a7b88708740>` 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 00:05:30.411535 134760609109824 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 0x7a7ba02d5b50>, ('items', <class 'orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeRestoreArgs'>): <orbax.checkpoint._src.handlers.pytree_checkpoint_handler.PyTreeCheckpointHandler object at 0x7a7ba02d5b50>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonSaveArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x7a7b88708740>, ('metrics', <class 'orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonRestoreArgs'>): <orbax.checkpoint._src.handlers.json_checkpoint_handler.JsonCheckpointHandler object at 0x7a7b88708740>}).
I0418 00:05:30.411863 134760609109824 abstract_checkpointer.py:35] orbax-checkpoint version: 0.11.34
I0418 00:05:30.411934 134760609109824 async_checkpointer.py:192] [process=1][thread=MainThread] Using barrier_sync_fn: <function get_barrier_sync_fn.<locals>._fn at 0x7a7b8849bc40> timeout: 1200 secs and primary_host=0 for async checkpoint writes
I0418 00:05:31.997223 134760609109824 checkpoint_manager.py:1812] Found 0 checkpoint steps in gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints
I0418 00:05:32.835627 134760609109824 checkpoint_manager.py:929] [process=1][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=10), 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_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints: <orbax.checkpoint.checkpoint_manager.CheckpointManager object at 0x7a7b88701790>
I0418 00:05:32.835787 134760609109824 checkpointing.py:301] Checkpoint manager created!
I0418 00:05:33.756928 134760609109824 nnx_wrappers.py:437] Unknown Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_norm_length', 'activation_embed').
I0418 00:05:33.757051 134760609109824 nnx_wrappers.py:437] Unknown Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None).
I0418 00:05:34.136436 134760609109824 attentions.py:1088] attentions/inputs_q Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed').
I0418 00:05:34.136548 134760609109824 attentions.py:1088] attentions/inputs_q Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None).
I0418 00:05:34.152654 134760609109824 attentions.py:1089] attentions/inputs_kv Logical: bfloat16[32,2048,2048]...................................... ('activation_batch', 'activation_attn_length', 'activation_attn_embed').
I0418 00:05:34.152714 134760609109824 attentions.py:1089] attentions/inputs_kv Physical: bfloat16[32,2048,2048]...................................... ('fsdp', None, None).
I0418 00:05:34.176204 134760609109824 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 00:05:34.176272 134760609109824 attentions.py:1154] attentions/query Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 00:05:34.192477 134760609109824 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 00:05:34.192537 134760609109824 attentions.py:1155] attentions/key Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 00:05:34.208591 134760609109824 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 00:05:34.208649 134760609109824 attentions.py:1156] attentions/value Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 00:05:34.233908 134760609109824 attentions.py:1197] attentions/out Logical: bfloat16[32,2048,16,128].................................... ('activation_batch', 'activation_attn_length', 'activation_heads', 'activation_kv').
I0418 00:05:34.233979 134760609109824 attentions.py:1197] attentions/out Physical: bfloat16[32,2048,16,128].................................... ('fsdp', None, None, None).
I0418 00:05:34.254607 134760609109824 linears.py:525] linears/x Logical: bfloat16[32,2048,7168]...................................... ('activation_batch', 'activation_length', 'activation_mlp').
I0418 00:05:34.254673 134760609109824 linears.py:525] linears/x Physical: bfloat16[32,2048,7168]...................................... ('fsdp', None, None).
I0418 00:05:34.470966 134760609109824 checkpointing.py:577] checkpoint manager exists so trying to load this run's existing checkpoint
I0418 00:05:34.471077 134760609109824 checkpointing.py:665] No existing checkpoints found, not restoring checkpoint.
fsdp: 32
I0418 00:05:35.895006 134760609109824 maxtext_utils.py:1654] params/params/decoder/decoder_norm/scale
Shape: float32[2048]
Logical: P('norm',)
Physical: (None,)
I0418 00:05:35.895130 134760609109824 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 00:05:35.895182 134760609109824 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 00:05:35.895238 134760609109824 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 00:05:35.895290 134760609109824 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 00:05:35.895329 134760609109824 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 00:05:35.895383 134760609109824 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 00:05:35.895438 134760609109824 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 00:05:35.895496 134760609109824 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 00:05:35.895536 134760609109824 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 00:05:35.895584 134760609109824 maxtext_utils.py:1654] params/params/decoder/logits_dense/kernel
Shape: float32[2048,32000]
Logical: P('embed_vocab', 'vocab')
Physical: ('fsdp', None)
I0418 00:05:35.895631 134760609109824 maxtext_utils.py:1654] params/params/token_embedder/embedding
Shape: float32[32000,2048]
Logical: P('vocab', 'embed_vocab')
Physical: (None, 'fsdp')
I0418 00:05:36.379543 134760609109824 train.py:155] train/xent Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length').
I0418 00:05:36.379639 134760609109824 train.py:155] train/xent Physical: float32[32,2048]............................................ ('fsdp', None).
I0418 00:05:36.394860 134760609109824 train.py:162] train/z_loss Logical: float32[32,2048]............................................ ('activation_embed_and_logits_batch', 'activation_length').
I0418 00:05:36.394920 134760609109824 train.py:162] train/z_loss Physical: float32[32,2048]............................................ ('fsdp', None).
I0418 00:05:47.364952 134760609109824 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 00:05:47.365742 134760609109824 metric_logger.py:301] number parameters: 1.104 billion
I0418 00:05:58.808921 134760609109824 checkpointing.py:772] Waiting for step 0 to finish before checkpoint...
I0418 00:05:58.961389 134760609109824 checkpointing.py:776] Waited 0.15244674682617188 seconds for step 0 to finish before starting checkpointing.
I0418 00:05:58.964130 134760609109824 checkpoint_manager.py:2009] [process=1][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning.
I0418 00:05:58.965722 134760609109824 checkpoint_manager.py:1512] [process=1] Saving checkpoint at step 0
I0418 00:05:58.967255 134760609109824 event_tracking.py:70] [process=1] [async] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints/0.
I0418 00:05:59.729075 134760609109824 signaling_client.py:364] Using JaxDistributedSignalingClient
I0418 00:05:59.730046 134760609109824 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array.
I0418 00:05:59.730105 134760609109824 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 00:06:00.006512 134760609109824 base_pytree_checkpoint_handler.py:154] [process=1][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.277511s
I0418 00:06:00.006682 134760609109824 base_pytree_checkpoint_handler.py:130] [process=1] /jax/orbax/write/blocking_gbytes_per_sec: 5.453 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.28287315368652344 s) (per-host)
I0418 00:06:00.006739 134760609109824 base_pytree_checkpoint_handler.py:768] [process=1][thread=MainThread] Initiated Pytree async_save. Time taken: 0.282940s (batch_requests_ready=0.002197s, total_serialization_initiated=0.280669s, others=0.000074s)
I0418 00:06:00.006834 134760609109824 composite_checkpoint_handler.py:715] [process=1][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 0.287574s (all_items=0.000019s, per_item={'items': '0.00001884'}, temp_paths=0.287555)
I0418 00:06:00.007558 134760609109824 event_tracking.py:125] [process=1] [async] Finished blocking save in 1.04 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints/0.
I0418 00:06:00.007841 134630598481664 async_checkpointer.py:76] [process=1][thread=async_save] Background save thread started. Deadline for this save operation is 2026-04-18 00:26:00.007800
I0418 00:06:00.018283 134760609109824 checkpoint_manager.py:1560] [process=1][thread=MainThread][step=0] Starting CheckpointManager Save Finalize thread=save_finalize
I0418 00:06:00.018570 134632231216896 async_checkpointer.py:280] [process=1][thread=save_finalize] Waiting for background save thread=async_save.
I0418 00:06:00.018725 134760609109824 standard_logger.py:34] {'step': 0, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': False, 'wait_for_prev_start_time': 1776470758.9641116, 'wait_for_prev_duration_secs': 6.198883056640625e-05, 'time_between_consecutive_saves_sec': None, 'checkpointer_blocking_start_time': 1776470758.965762, 'checkpointer_blocking_duration_secs': 1.0422389507293701, 'get_old_steps_start_time': 1776470760.0080237, 'get_old_steps_duration_secs': 2.8371810913085938e-05, 'checkpoint_manager_blocking_start_time': 1776470758.961883, 'checkpoint_manager_blocking_duration_secs': 1.0568056106567383}
I0418 00:06:00.018832 134760609109824 checkpointing.py:408] Started an asynchronous checkpoint save for step 0
I0418 00:06:00.018892 134760609109824 max_utils.py:750]
Memstats: After params initialized:
I0418 00:06:00.018943 134760609109824 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_2(process=1,(2,0,0,0))
I0418 00:06:00.018978 134760609109824 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_3(process=1,(3,0,0,0))
I0418 00:06:00.019003 134760609109824 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_6(process=1,(2,1,0,0))
I0418 00:06:00.019028 134760609109824 max_utils.py:756] Using (GB) 0.43 / 31.25 (1.376000%) on TPU_7(process=1,(3,1,0,0))
I0418 00:06:00.328201 134760609109824 metric_logger.py:196] completed step: 0, seconds: 11.443, TFLOP/s/device: 1.187, Tokens/s/device: 178.973, total_weights: 65536, loss: 10.874, lm_loss: 10.874, perplexity: 52779.875
I0418 00:06:00.504634 134760609109824 metric_logger.py:196] completed step: 1, seconds: 1.518, TFLOP/s/device: 8.952, Tokens/s/device: 1349.365, total_weights: 65536, loss: 10.874, lm_loss: 10.874, perplexity: 52779.875
I0418 00:06:00.906298 134760609109824 metric_logger.py:196] completed step: 2, seconds: 0.029, TFLOP/s/device: 466.511, Tokens/s/device: 70317.597, total_weights: 65536, loss: 10.262, lm_loss: 10.262, perplexity: 28637.129
I0418 00:06:01.053775 134760609109824 metric_logger.py:196] completed step: 3, seconds: 0.402, TFLOP/s/device: 33.778, Tokens/s/device: 5091.399, total_weights: 65536, loss: 9.734, lm_loss: 9.734, perplexity: 16889.203
I0418 00:06:01.348857 134760609109824 metric_logger.py:196] completed step: 4, seconds: 0.153, TFLOP/s/device: 88.972, Tokens/s/device: 13410.777, total_weights: 65536, loss: 9.277, lm_loss: 9.277, perplexity: 10694.614
I0418 00:06:01.354846 134760609109824 metric_logger.py:196] completed step: 5, seconds: 0.147, TFLOP/s/device: 92.199, Tokens/s/device: 13897.277, total_weights: 65536, loss: 8.892, lm_loss: 8.892, perplexity: 7270.717
I0418 00:06:05.120651 2816 google_auth_provider.cc:181] Running on GCE, using service account 562977990677-compute@developer.gserviceaccount.com
I0418 00:06:06.981716 134630618089216 array_metadata_store.py:203] [process=1][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints/0/items/array_metadatas/process_1
I0418 00:06:25.744389 134760609109824 metric_logger.py:196] completed step: 6, seconds: 0.296, TFLOP/s/device: 45.955, Tokens/s/device: 6926.852, total_weights: 65536, loss: 8.592, lm_loss: 8.592, perplexity: 5390.759
I0418 00:06:25.891682 134760609109824 metric_logger.py:196] completed step: 7, seconds: 24.243, TFLOP/s/device: 0.560, Tokens/s/device: 84.479, total_weights: 65536, loss: 8.384, lm_loss: 8.384, perplexity: 4376.905
I0418 00:06:26.039178 134760609109824 metric_logger.py:196] completed step: 8, seconds: 0.152, TFLOP/s/device: 89.279, Tokens/s/device: 13457.128, total_weights: 65536, loss: 8.255, lm_loss: 8.255, perplexity: 3846.406
I0418 00:06:26.185644 134760609109824 checkpointing.py:772] Waiting for step 9 to finish before checkpoint...
I0418 00:06:26.186290 134760609109824 checkpointing.py:776] Waited 0.0006680488586425781 seconds for step 9 to finish before starting checkpointing.
I0418 00:06:26.188531 134760609109824 checkpoint_manager.py:2020] [process=1][thread=MainThread][step=0][wait_until_finished] Waiting for Save Finalize thread (save_finalize) to complete.
I0418 00:06:35.835058 134630598481664 base_pytree_checkpoint_handler.py:130] [process=1] /jax/orbax/write/gbytes_per_sec: 43.743 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 36.11120963096619 s) (per-host)
I0418 00:06:35.835177 134630598481664 async_checkpointer.py:90] [process=1][thread=async_save] 3 Handler Commit operations completed. Time taken: 35.827222s.
I0418 00:06:47.946554 134630598481664 async_checkpointer.py:160] [process=1][thread=async_save] Background save thread done. Time taken: 47.938583s.
I0418 00:06:47.946844 134632231216896 async_checkpointer.py:288] [process=1][thread=save_finalize] Done with waiting for background save thread=async_save.
I0418 00:06:47.946973 134632231216896 async_checkpointer.py:298] [process=1][thread=save_finalize] No errors found in background save thread=async_save.
I0418 00:06:47.947023 134632231216896 checkpoint_manager.py:2137] [process=1][thread=save_finalize][step=0] CheckpointManager Save Finalize is syncing with other hosts...
I0418 00:06:47.951328 134632231216896 checkpoint_manager.py:2146] [process=1][thread=save_finalize][step=0] CheckpointManager Save Finalize is done on all hosts.
I0418 00:06:47.951544 134760609109824 checkpoint_manager.py:2032] [process=1][thread=MainThread][step=0][wait_until_finished] Done waiting for Save Finalize thread (save_finalize) running at step=0.
W0418 00:06:47.951675 134760609109824 checkpoint_manager.py:1452] Waiting for previous save to complete took 21.763145 seconds. If this number is high, consider checkpointing less frequently.
I0418 00:06:47.953551 134760609109824 checkpoint_manager.py:1512] [process=1] Saving checkpoint at step 9
I0418 00:06:47.955726 134760609109824 event_tracking.py:70] [process=1] [async] Started save checkpoint @ gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints/9.
I0418 00:06:48.672383 134760609109824 jax_array_handlers.py:360] Scheduling D2H of 39 prioritized jax.Array.
I0418 00:06:48.672488 134760609109824 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 00:06:48.712367 134760609109824 base_pytree_checkpoint_handler.py:154] [process=1][thread=MainThread] Initiated "orbax.checkpoint._src.serialization.jax_array_handlers.ArrayHandler".serialize. Time taken: 0.041084s
I0418 00:06:48.712543 134760609109824 base_pytree_checkpoint_handler.py:130] [process=1] /jax/orbax/write/blocking_gbytes_per_sec: 34.693 GiB/s (total gbytes: 1.5 GiB) (time elapsed: 0.044463396072387695 s) (per-host)
I0418 00:06:48.712596 134760609109824 base_pytree_checkpoint_handler.py:768] [process=1][thread=MainThread] Initiated Pytree async_save. Time taken: 0.044527s (batch_requests_ready=0.001728s, total_serialization_initiated=0.042727s, others=0.000072s)
I0418 00:06:48.712686 134760609109824 composite_checkpoint_handler.py:715] [process=1][thread=MainThread] Initiated CompositeCheckpointHandler.async_save. Time taken: 0.048767s (all_items=0.000015s, per_item={'items': '0.00001550'}, temp_paths=0.048752)
I0418 00:06:48.713367 134760609109824 event_tracking.py:125] [process=1] [async] Finished blocking save in 0.76 seconds. Continuing save @ gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints/9.
I0418 00:06:48.713727 134632231216896 async_checkpointer.py:76] [process=1][thread=async_save] Background save thread started. Deadline for this save operation is 2026-04-18 00:26:48.713691
I0418 00:06:48.715674 134760609109824 checkpoint_manager.py:1560] [process=1][thread=MainThread][step=9] Starting CheckpointManager Save Finalize thread=save_finalize
I0418 00:06:48.715971 134631722579712 async_checkpointer.py:280] [process=1][thread=save_finalize] Waiting for background save thread=async_save.
I0418 00:06:48.716114 134760609109824 standard_logger.py:34] {'step': 9, 'event_type': 'save', 'directory': 'gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints', 'reached_preemption': False, 'preemption_received_at': None, 'synchronous': False, 'wait_for_prev_start_time': 1776470786.188502, 'wait_for_prev_duration_secs': 21.763144731521606, 'time_between_consecutive_saves_sec': None, 'checkpointer_blocking_start_time': 1776470807.9535913, 'checkpointer_blocking_duration_secs': 0.7602841854095459, 'get_old_steps_start_time': 1776470808.7138996, 'get_old_steps_duration_secs': 3.0994415283203125e-05, 'checkpoint_manager_blocking_start_time': 1776470786.186538, 'checkpoint_manager_blocking_duration_secs': 22.529542207717896}
I0418 00:06:48.716280 134760609109824 checkpointing.py:408] Started an asynchronous checkpoint save for step 9
I0418 00:06:48.716331 134760609109824 checkpoint_manager.py:2020] [process=1][thread=MainThread][step=9][wait_until_finished] Waiting for Save Finalize thread (save_finalize) to complete.
I0418 00:06:56.345995 134630618089216 array_metadata_store.py:203] [process=1][thread=array_type_handler] Wrote 39 array_metadata.ArrayMetadata to gs://lance-maxtext/linen_ckpt_xpk_main_20260417_235819/linen_xpk_main_20260417_235819_02_synthetic/checkpoints/9/items/array_metadatas/process_1
I0418 00:07:30.568964 134632231216896 base_pytree_checkpoint_handler.py:130] [process=1] /jax/orbax/write/gbytes_per_sec: 37.698 MiB/s (total gbytes: 1.5 GiB) (time elapsed: 41.90084767341614 s) (per-host)
I0418 00:07:30.569087 134632231216896 async_checkpointer.py:90] [process=1][thread=async_save] 3 Handler Commit operations completed. Time taken: 41.855247s.
I0418 00:07:40.653762 134632231216896 async_checkpointer.py:160] [process=1][thread=async_save] Background save thread done. Time taken: 51.939905s.
I0418 00:07:40.654027 134631722579712 async_checkpointer.py:288] [process=1][thread=save_finalize] Done with waiting for background save thread=async_save.
I0418 00:07:40.654149 134631722579712 async_checkpointer.py:298] [process=1][thread=save_finalize] No errors found in background save thread=async_save.
I0418 00:07:40.654198 134631722579712 checkpoint_manager.py:2137] [process=1][thread=save_finalize][step=9] CheckpointManager Save Finalize is syncing with other hosts...
I0418 00:07:40.656504 134631722579712 checkpoint_manager.py:2146] [process=1][thread=save_finalize][step=9] CheckpointManager Save Finalize is done on all hosts.
I0418 00:07:40.656684 134760609109824 checkpoint_manager.py:2032] [process=1][thread=MainThread][step=9][wait_until_finished] Done waiting for Save Finalize thread (save_finalize) running at step=9.
I0418 00:07:40.656843 134760609109824 checkpoint_manager.py:2009] [process=1][thread=MainThread][wait_until_finished] No Save Finalize thread to wait for. Returning.
I0418 00:07:40.657910 134760609109824 metric_logger.py:196] completed step: 9, seconds: 0.147, TFLOP/s/device: 92.292, Tokens/s/device: 13911.248, total_weights: 65536, loss: 8.179, lm_loss: 8.179, perplexity: 3564.635
Per train step:
Total TFLOPs: 13.59
split as 93.93% learnable weight flops and 6.07% attention flops
XPK End: Sat Apr 18 00:07:49 UTC 2026
EXIT_CODE=0