2026-07-22T04:25:09.591887Z  INFO compiling kernel source=/srv/home/gc-sdk/ipu-stack/crates/ipu-runtime/../../device/flash_attention_f16.cpp name="flash-attention-codelet" target=ipu21
2026-07-22T04:25:10.674509Z  INFO kernel artifact created object=/srv/home/.cache/ipu-stack/kernels/f4887a1d9e2085ed5a09c6af88b2c53ff1aec0ae041bafbab3644bcfa8544b45/kernel.o metadata=/srv/home/.cache/ipu-stack/kernels/f4887a1d9e2085ed5a09c6af88b2c53ff1aec0ae041bafbab3644bcfa8544b45/kernel.json
2026-07-22T04:25:10.674659Z  INFO compiling kernel source=/srv/home/gc-sdk/ipu-stack/crates/ipu-runtime/../../device/gemm_f16_64_amp.S name="attention-qk" target=ipu21
2026-07-22T04:25:10.734907Z  INFO kernel artifact created object=/srv/home/.cache/ipu-stack/kernels/4f2d534c97aa96df15f4b15158bd257e09a0521e1dabe46b064fea77a62d0aa6/kernel.o metadata=/srv/home/.cache/ipu-stack/kernels/4f2d534c97aa96df15f4b15158bd257e09a0521e1dabe46b064fea77a62d0aa6/kernel.json
2026-07-22T04:25:10.734980Z  INFO compiling kernel source=/srv/home/gc-sdk/ipu-stack/crates/ipu-runtime/../../device/gemm_f16_64_amp.S name="attention-pv" target=ipu21
2026-07-22T04:25:10.790823Z  INFO kernel artifact created object=/srv/home/.cache/ipu-stack/kernels/0854d8cac25f6ba1602266d2d71e548b1f0de731fee599c949a0159dab267951/kernel.o metadata=/srv/home/.cache/ipu-stack/kernels/0854d8cac25f6ba1602266d2d71e548b1f0de731fee599c949a0159dab267951/kernel.json
2026-07-22T04:25:10.857337Z  INFO lowered exchange schedule phases=8 launches=8
2026-07-22T04:25:11.121729Z  INFO lowered per-tile programs tiles=1472
2026-07-22T04:25:11.182696Z  INFO linking tile image objects=6 base=0x4c010 entry=ipu_stack_static_start
2026-07-22T04:25:11.182934Z  INFO tile image linked bytes=8528 symbols=30 entry=0x4c014
2026-07-22T04:25:11.182980Z  INFO linking tile image objects=6 base=0x4c010 entry=ipu_stack_static_start
2026-07-22T04:25:11.183117Z  INFO tile image linked bytes=8528 symbols=30 entry=0x4c014
2026-07-22T04:25:11.185653Z  INFO linking tile image objects=6 base=0x4c010 entry=ipu_stack_static_start
2026-07-22T04:25:11.185744Z  INFO tile image linked bytes=400 symbols=14 entry=0x4c014
2026-07-22T04:25:11.208656Z  INFO packed segmented host runtime ranges=[(361416, 363176), (363176, 368036), (368040, 368052), (368056, 368068), (368072, 368084), (368088, 368100), (368104, 368116), (368120, 368132), (368136, 368148), (368152, 368164), (368168, 368180), (368184, 368196), (368200, 368212), (368216, 368576), (378768, 378948), (378952, 379044), (379048, 379108), (379112, 379260)] first_plan="0x5c8a8" first_packet="0x59d40" first_run_table="0x59da8" worker_sync=0x583c8 completion=0x583c8
2026-07-22T04:25:11.412918Z  INFO linking tile image objects=6 base=0x60000 entry=ipu_stack_static_start
2026-07-22T04:25:11.413118Z  INFO tile image linked bytes=8528 symbols=30 entry=0x60004
2026-07-22T04:25:11.413150Z  INFO linking tile image objects=6 base=0x60000 entry=ipu_stack_static_start
2026-07-22T04:25:11.413285Z  INFO tile image linked bytes=8528 symbols=30 entry=0x60004
2026-07-22T04:25:11.414975Z  INFO linking tile image objects=6 base=0x60000 entry=ipu_stack_static_start
2026-07-22T04:25:11.415056Z  INFO tile image linked bytes=400 symbols=14 entry=0x60004
2026-07-22T04:25:11.418348Z  INFO largest generated tile program breakdown logical_tile=274 generated_bytes=2016 generated_exchange_bytes=96 generated_compute_bytes=1492 generated_unrolled_compute_calls=93 generated_fused_compute_calls=0 generated_compute_argument_words=1 generated_fused_run_bytes=0 generated_fused_runs=0 generated_host_and_control_bytes=428 support_image_bytes=8528 exchange_plan_bytes=968 host_plan_and_state_bytes=7592
2026-07-22T04:25:11.532984Z  INFO packaged static executable graph tiles=1472 exchange_launches=8 host_inputs=2 host_outputs=1 max_program_bytes=2016 distinct_image_bases=3 minimum_image_base=0x60000 maximum_image_base=0x61ca0 minimum_program_base=0x5c000 maximum_program_base=0x5c000
2026-07-22T04:25:11.660663Z  INFO packaged FP16 FlashAttention batch_size=4 query_sequence_length=729 sequence_length=729 hidden_size=1152 heads=16 head_dimension=72 tasks=1344 query_block_rows=35 key_block_rows=32 padded_head_dimension=80 key_block_columns=32 exchange_phases=23 input_bytes=22538240
2026-07-22T04:25:11.660701Z  INFO opening IPU device path="/dev/ipu0"
2026-07-22T04:25:11.660746Z  INFO IPU device attached path=/dev/ipu0
2026-07-22T04:25:11.660749Z  INFO initializing IPU device
2026-07-22T04:25:11.668592Z  INFO IPU device initialized
2026-07-22T04:25:11.668598Z  INFO replaying device configuration register_writes=2003
2026-07-22T04:25:11.672806Z  INFO loading application tile_count=1472 final_mark=23
2026-07-22T04:25:11.877908Z  INFO application loaded and initial synchronization completed tile_count=1472
2026-07-22T04:25:11.881492Z  INFO starting host exchange session startup_mark=23
2026-07-22T04:25:11.881507Z  INFO attaching host exchange pages pages=2
2026-07-22T04:25:11.882310Z  INFO host exchange session started
2026-07-22T04:25:11.883120Z  INFO invoking streaming host exchange call call="graph" command=0 phases=22527
2026-07-22T04:25:40.820691Z  INFO FP16 FlashAttention passed host softmax reference batch_size=4 query_sequence_length=729 sequence_length=729 hidden_size=1152 heads=16 max_abs_error=8.046627044677734e-5 rmse=8.730956324143335e-6 max_error_limit=0.20000000298023224