rocm_jax/jax/_src/cloud_tpu_init.py
Michael Whittaker 5cb29949d4 Warn the user if transparent huge pages aren't enabled.
PiperOrigin-RevId: 735431881
2025-03-10 10:37:58 -07:00

135 lines
4.7 KiB
Python

# Copyright 2021 The JAX Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import datetime
import os
import re
import warnings
from jax import version
from jax._src import config
from jax._src import hardware_utils
running_in_cloud_tpu_vm: bool = False
def maybe_import_libtpu():
try:
# pylint: disable=import-outside-toplevel
# pytype: disable=import-error
import libtpu
# pytype: enable=import-error
# pylint: enable=import-outside-toplevel
except ImportError:
return None
else:
return libtpu
def get_tpu_library_path() -> str | None:
path_from_env = os.getenv("TPU_LIBRARY_PATH")
if path_from_env is not None and os.path.isfile(path_from_env):
return path_from_env
libtpu_module = maybe_import_libtpu()
if libtpu_module is not None:
return libtpu_module.get_library_path()
return None
def jax_force_tpu_init() -> bool:
return 'JAX_FORCE_TPU_INIT' in os.environ
def cloud_tpu_init() -> None:
"""Automatically sets Cloud TPU topology and other env vars.
**This must be called before the TPU runtime is loaded, which happens as soon
as JAX's C++ backend is loaded! I.e. call this before xla_bridge or xla_client
is imported.**
Safe to call in non-Cloud TPU environments.
Some of these environment variables are used to tell the TPU runtime what kind
of mesh topology to use. It assumes a single-host topology by default, so we
manually set them here to default to the full pod slice if applicable.
This will not set any env vars if a single topology-related env var is already
set.
"""
global running_in_cloud_tpu_vm
# Exit early if we're not running on a Cloud TPU VM or libtpu isn't installed.
libtpu_path = get_tpu_library_path()
num_tpu_chips, tpu_id = hardware_utils.num_available_tpu_chips_and_device_id()
if (
tpu_id is not None
and tpu_id >= hardware_utils.TpuVersion.v5e
and not hardware_utils.transparent_hugepages_enabled()
):
warnings.warn(
'Transparent hugepages are not enabled. TPU runtime startup and'
' shutdown time should be significantly improved on TPU v5e and newer.'
' If not already set, you may need to enable transparent hugepages in'
' your VM image (sudo sh -c "echo always >'
' /sys/kernel/mm/transparent_hugepage/enabled")'
)
if (libtpu_path is None or num_tpu_chips == 0) and not jax_force_tpu_init():
return
running_in_cloud_tpu_vm = True
os.environ.setdefault('GRPC_VERBOSITY', 'ERROR')
os.environ.setdefault('TPU_ML_PLATFORM', 'JAX')
os.environ.setdefault('TPU_ML_PLATFORM_VERSION', version.__version__)
os.environ.setdefault('ENABLE_RUNTIME_UPTIME_TELEMETRY', '1')
if '--xla_tpu_use_enhanced_launch_barrier' not in os.environ.get('LIBTPU_INIT_ARGS', ''):
os.environ['LIBTPU_INIT_ARGS'] = os.environ.get('LIBTPU_INIT_ARGS','') + ' --xla_tpu_use_enhanced_launch_barrier=true'
# this makes tensorstore serialization work better on TPU
os.environ.setdefault('TENSORSTORE_CURL_LOW_SPEED_TIME_SECONDS', '60')
os.environ.setdefault('TENSORSTORE_CURL_LOW_SPEED_LIMIT_BYTES', '256')
# If the JAX_PLATFORMS env variable isn't set, config.jax_platforms defaults
# to None. In this case, we set it to 'tpu,cpu' to ensure that JAX uses the
# TPU backend.
if config.jax_platforms.value is None:
config.update('jax_platforms', 'tpu,cpu')
if config.jax_pjrt_client_create_options.value is None:
config.update(
'jax_pjrt_client_create_options',
f'ml_framework_name:JAX;ml_framework_version:{version.__version__}'
)
def is_cloud_tpu_older_than(year: int, month: int, day: int):
# We import locally because the functions above must run before the runtime
# modules are imported.
from jax._src import xla_bridge # pytype: disable=import-error
date = datetime.date(year, month, day)
if not running_in_cloud_tpu_vm:
return False
# The format of Cloud TPU platform_version is like:
# PJRT C API
# TFRT TPU v2
# Built on Oct 30 2023 03:04:42 (1698660263) cl/577737722
platform_version = xla_bridge.get_backend().platform_version.split('\n')[-1]
results = re.findall(r'\(.*?\)', platform_version)
if len(results) != 1:
return True
build_date = date.fromtimestamp(int(results[0][1:-1]))
return build_date < date