Proof-of-concept: Shard-local logging from JAX. #25912
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As discussed in #25842, since JAX's current logging mechanisms (e.g. `jax.debug.print`) are built on callbacks, logging a sharded array requires an expensive all-gather operation. It would sometimes be useful to be able to separately print the local data shard on each worker. These parallel changes to XLA and JAX are meant as an experiment to demonstrate the custom GSPMD partitioning logic needed for this behavior. I'm currently using a new FFI handler that doesn't do anything, but this is sufficient to test the partitioning logic. It should be feasible to apply this same logic to a custom call encapsulating a callback. PiperOrigin-RevId: 715862954
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Proof-of-concept: Shard-local logging from JAX.
As discussed in #25842, since JAX's current logging mechanisms (e.g.
jax.debug.print) are built on callbacks, logging a sharded array requires an expensive all-gather operation. It would sometimes be useful to be able to separately print the local data shard on each worker.These parallel changes to XLA and JAX are meant as an experiment to demonstrate the custom GSPMD partitioning logic needed for this behavior. I'm currently using a new FFI handler that doesn't do anything, but this is sufficient to test the partitioning logic. It should be feasible to apply this same logic to a custom call encapsulating a callback.