* keep track of all known config.State objects so we can find them by name.
* change `@jtu.with_config` to default to setting thread-local configurations.
* add a `@jtu.with_global_config` for those things that truly need to be set globally.
* add a `@jtu.thread_local_config_context` that overrides thread-local configuration options, just as `jtu.global_config_context` overrides global configuration options.
* change the pretty printer color option to be a State so it can be set locally.
* tag a number of tests as thread-hostile, in particular tests that check counters for numbers of compilations, rely on garbage collection having particular semantics, or look at log output.
PiperOrigin-RevId: 713411171
Add a sharding rule string and trailing factor_sizes to def_partition, to
provide a sharding rule specification when Shardy is used. We use this
information to construct a SdyShardingRule and invoke SdyShardingRule.build
during MLIR lowering.
Extend custom_partitioner tests in pjit_test.py for Shardy sharding rule.
PiperOrigin-RevId: 713399604
If PartitionSpec is passed, the mesh is read from the context. The primitives though take `NamedSharding` only. The conversion from `PartitionSpec` to `NamedSharding` happens above `.bind`.
We also raise an error if `PartitionSpec` contain mesh axis names that are of type Auto or Collective for the above functions.
PiperOrigin-RevId: 713352542
Before if something went wrong during JAX lowering, then instead of verification catching this, the pass would making the error message difficult to read and incorrectly pointing to the pass as the source of the error. For example
```
File "jax/_src/interpreters/mlir.py", line 1211, in lower_jaxpr_to_module
pipeline.run(ctx.module.operation)
MLIRError: Failure while executing pass pipeline:
error:
...
'sdy.sharding_constraint' op sharding doesn't match tensor rank: 0 != 2
...
see current operation: %2 = "sdy.sharding_constraint"(%1) <{sharding = #sdy.sharding<@mesh, []>}> : (tensor<8x2xf64>) -> tensor<8x2xf64>
```
PiperOrigin-RevId: 713314555
This change does not yet do the work necessary to make any tests pass with threading enabled, which will come in future changes.
This approach is broadly inspired by a6d205dd4c/testtools/testsuite.py (L113) and by unittest-ft.
We add a custom TestResult class that batches up any test result actions and applies them under a lock. We also add a custom TestSuite class that runs individual test cases in parallel using a thread-pool.
We need a reader-writer lock to implement a `@jtu.thread_hostile_test` decorator, which we do by adding bindings around absl::Mutex to jaxlib.
PiperOrigin-RevId: 713312937
This change prepares for upcoming changes in which we run tests in parallel using threads, which we are doing partially to test free threading but also partially to speed up TPU tests via thread-parallelism.
If independent tests run in parallel in no particular order, there's no natural scope around which to call setUpClass or SetUpModule. But for JAX tests this never seems necessary: we can just do the same work in setUp() or do it globally.
PiperOrigin-RevId: 713296722
This subsumes (and ultimately will deprecate) overriding the number of CPU devices via XLA_FLAGS.
In addition, replace the test utility jtu.set_host_platform_device_count with jtu.request_cpu_devices(...), which sets or increases the flag's value. This both removes the need for an overly complicated context stack, and prepares for removing remaining uses of setUpModule as part of work parallelizing the test suite with threads.
PiperOrigin-RevId: 713272197
This often lets us avoid ambiguities between selecting the (8, 128) and (16, 128) tiling,
by biasing the layout inference to prefer the latter.
PiperOrigin-RevId: 713270421
Log such events for log_elapsed_time.
The rationale for not replacing durations with it is that it appears that
record_event_duration_secs() is widely used outside of the code of JAX itself.
PiperOrigin-RevId: 713167192
It turns out that the backend is rarely needed when lowering, e.g.,
for lowering callbacks. Whenever we need the backend for lowering,
we must be in single-platform lowering mode (`len(platforms) == 1`)
and we can look up the backend from `platforms[0]`.
However, in some rare cases we can have a custom `XlaBackend` whose
platform matches `platforms[0]`. We rename `backend_or_name` to just `backend`
and we restrict its type to be an optional `XlaBackend` (not a platform
string).
PiperOrigin-RevId: 712926140
Previously with 4 heads the reference function `ref` would allocate 32 GiB since it materializes large intermediate tensors. That causes CI on an 80GB H100 to run out of memory when 4 tests run in parallel. `num_q_heads=2` allows us to test multiple heads while cutting memory in half.
