task.py 24 KB

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  1. ## @package task
  2. # Module caffe2.python.task
  3. from caffe2.python import core, context
  4. from caffe2.python.schema import Field, from_blob_list
  5. from collections import defaultdict
  6. from copy import copy
  7. from future.utils import viewitems
  8. def _merge_node_kwargs(a, b):
  9. # TODO(azzolini): consistency checks
  10. if a is None:
  11. return b
  12. if b is None:
  13. return a
  14. c = copy(a)
  15. c.update(b)
  16. return c
  17. class Cluster(context.DefaultManaged):
  18. """
  19. Context that keeps track of all the node names used.
  20. Users shouldn't have to use them directly, since a Cluster is automatically
  21. generated at the first usage of 'Node'.
  22. """
  23. def __init__(self):
  24. # list instead of set to keep order
  25. self._nodes = []
  26. self._node_kwargs = {}
  27. def add_node(self, node):
  28. if str(node) not in self._nodes:
  29. self._nodes.append(str(node))
  30. self._node_kwargs[str(node)] = _merge_node_kwargs(
  31. node.kwargs(),
  32. self._node_kwargs.get(str(node)))
  33. def nodes(self):
  34. """
  35. Returns the list of unique node names used within this context.
  36. """
  37. return self._nodes
  38. def node_kwargs(self):
  39. return self._node_kwargs
  40. def __repr__(self):
  41. return "Cluster(nodes={}, node_kwargs={})".format(
  42. self.nodes(), self.node_kwargs())
  43. class Node(context.DefaultManaged):
  44. """
  45. A Node context is used to indicate that all Tasks instantiated within will
  46. run on the given node name. (Only the name of the node actually counts.)
  47. Example:
  48. with TaskGroup() as tg:
  49. with Node('node1'):
  50. s1 = execution_step(...)
  51. Task(step=s1)
  52. with Node('node2'):
  53. s2 = execution_step(...)
  54. with Node('node1'):
  55. s3 = execution_step(...)
  56. In this example, all three execution steps will run in parallel.
  57. Moreover, s1 and s3 will run on the same node, and can see each
  58. others blobs.
  59. Additionally, a Node can be passed implementation-specific kwargs,
  60. in order to specify properties of the node.
  61. """
  62. def __init__(self, node='local', **kwargs):
  63. self._name = str(node)
  64. self._kwargs = kwargs
  65. Cluster.current().add_node(self)
  66. def __str__(self):
  67. return self._name
  68. def __repr__(self):
  69. return "Node(name={}, kwargs={})".format(self._name, self._kwargs)
  70. def kwargs(self):
  71. return self._kwargs
  72. class WorkspaceType(object):
  73. """
  74. Determines whether tasks of a TaskGroup will run directly at the global
  75. workspace, which is kept alive across runs, or whether a new child
  76. workspace will be created for the run and destroyed afterwards.
  77. """
  78. PRIVATE = 'private'
  79. GLOBAL = 'global'
  80. def get_setup_nets(key, steps_or_nets, target):
  81. init_net = core.Net(key + '/init')
  82. exit_net = core.Net(key + '/exit')
  83. init_nets = []
  84. exit_nets = []
  85. objs = []
  86. for step_or_net in steps_or_nets:
  87. if hasattr(step_or_net, 'get_all_attributes'):
  88. objs += step_or_net.get_all_attributes(key)
  89. elif hasattr(step_or_net, 'get_attributes'):
  90. objs += step_or_net.get_attributes(key)
  91. for obj in objs:
  92. # these are needed in order to allow nesting of TaskGroup, which
  93. # is a feature not yet implemented.
  94. if hasattr(obj, '_setup_used') and obj._setup_used:
  95. continue
  96. if hasattr(obj, '_setup_target') and obj._setup_target != target:
  97. continue
  98. if hasattr(obj, 'setup'):
  99. nets = obj.setup(init_net)
  100. if isinstance(nets, (list, tuple)):
  101. init_nets += nets
  102. elif isinstance(nets, (core.Net, core.ExecutionStep)):
  103. init_nets.append(nets)
  104. elif nets is not None:
  105. raise TypeError('Unsupported type for setup: %s' % type(nets))
  106. obj._setup_used = True
  107. if hasattr(obj, 'exit'):
  108. nets = obj.exit(exit_net)
  109. if isinstance(nets, (list, tuple)):
  110. exit_nets += nets
  111. elif isinstance(nets, (core.Net, core.ExecutionStep)):
  112. exit_nets.append(nets)
  113. elif nets is not None:
  114. raise TypeError('Unsupported type for setup: %s' % type(nets))
  115. obj._setup_used = True
  116. if len(init_net.Proto().op) > 0:
  117. init_nets.insert(0, init_net)
  118. if len(exit_net.Proto().op) > 0:
  119. exit_nets.insert(0, exit_net)
  120. return init_nets, exit_nets
  121. def add_setup_steps(step, init_nets, exit_nets, name):
  122. if not init_nets and not exit_nets:
  123. return step
  124. steps = []
  125. if init_nets:
  126. steps.append(core.execution_step('%s:init' % name, init_nets))
  127. steps.append(step)
  128. if len(exit_nets) > 0:
  129. steps.append(core.execution_step('%s:exit' % name, exit_nets))
  130. return core.execution_step(name, steps)
  131. class TaskGroup(context.Managed):
  132. """
  133. Context that gathers tasks which will run concurrently, potentially on
  134. multiple nodes. All tasks in the same node will share the same workspace
  135. and thus can share blobs, while tasks running in different nodes won't
  136. be able to directly share data.
  137. All tasks of the task group will start concurrently, and the task group
  138. will finish execution when the last task of the group finishes.
  139. Example:
  140. # suppose that s1 ... s5 are execution steps or nets.
  141. with TaskGroup() as tg:
  142. # these tasks go to default node 'local'
  143. Task(step=s1)
  144. Task(step=s2)
  145. with Node('n2'):
  146. Task(step=s3)
  147. with Node('n1'):
  148. Task(step=s4)
  149. with Node('n2'):
  150. Task(step=s5)
  151. # this will run all steps in parallel.
  152. # s1 and s2 will run at default node 'local'
  153. # s3 and s5 will run at node 'n2'
  154. # s4 will run at node 'n1'
  155. session.run(tg)
  156. """
  157. LOCAL_SETUP = 'local_setup'
  158. def __init__(self, workspace_type=None):
  159. self._plan_cache = None
  160. self._tasks = []
  161. self._already_used = False
  162. self._prev_active = None
  163. self._tasks_to_add = []
  164. self._report_nets = {}
  165. self._report_steps = []
  166. self._workspace_type = workspace_type
  167. self._tasks_by_node = None
  168. self._remote_nets = []
  169. def add_remote_net(self, net):
  170. self._remote_nets.append(net)
  171. def remote_nets(self):
  172. return self._remote_nets
  173. def add(self, task):
  174. assert not self._already_used, (
  175. 'Cannot add Task to an already used TaskGroup.')
  176. assert (
  177. self._workspace_type is None or
  178. task._workspace_type is None or
  179. self._workspace_type == task._workspace_type)
  180. if task._workspace_type is None:
  181. task._workspace_type = (
  182. self._workspace_type or WorkspaceType.PRIVATE)
  183. if self._workspace_type is None:
  184. self._workspace_type = task._workspace_type
  185. task._notify_used()
  186. self._tasks.append(task)
  187. def tasks(self):
  188. for task in self._tasks_to_add:
  189. self.add(task)
  190. self._tasks_to_add = []
  191. self._already_used = True
  192. return self._tasks
  193. def num_registered_tasks(self):
  194. return len(self._tasks_to_add) + len(self._tasks)
  195. def used_nodes(self):
  196. # use list to keep order
  197. used = []
  198. for task in self._tasks + self._tasks_to_add:
  199. if task.node not in used:
  200. used.append(task.node)
  201. return used
  202. def report_step(self, step=None, node=None, interval_ms=1000):
  203. """
  204. Add a "report step" to this TaskGroup. This step will run repeatedly
  205. every `interval_ms` milliseconds for the duration of the TaskGroup
  206. execution on each of the nodes. It is guaranteed that this step
  207. will be run at least once after every Task in the node has finished.
  208. """
  209. step = core.to_execution_step(step)
  210. step.RunEveryMillis(interval_ms)
  211. self._report_steps.append((str(node or Node.current(node)), step))
  212. def report_net(self, net=None, node=None, report_interval=5):
  213. """
  214. DEPRECATED. Use report_step instead.
  215. """
  216. node = str(node or Node.current(node))
  217. assert net is None or node not in self._report_nets
  218. if node not in self._report_nets:
  219. self._report_nets[node] = (
  220. net if net else core.Net('%s/reporter' % node),
  221. report_interval)
  222. return self._report_nets[node][0]
  223. def tasks_by_node(self, node_remap=None):
  224. # tasks_by_node can't be called twice because the setup won't
  225. # work properly a second time.
  226. node_map = {}
  227. for task in self.tasks():
  228. node_map[task.node] =\
  229. node_remap(task.node) if node_remap else task.node
  230. if self._tasks_by_node is not None:
  231. tasks_by_node, prev_node_map = self._tasks_by_node
  232. assert prev_node_map == node_map, (
  233. 'Cannot call tasks_by_node multiple times.')
  234. return tasks_by_node
  235. # now we have report_steps. report_net is deprecated
  236. for node, (net, interval) in viewitems(self._report_nets):
  237. self.report_step(net, node=node, interval_ms=interval * 1000)
  238. self._report_nets = {}
  239. tasks_by_node = defaultdict(list)
  240. for task in self.tasks():
  241. mapped_node = node_map[task.node]
  242. tasks_by_node[mapped_node].append(task)
  243. report_steps_by_node = defaultdict(list)
  244. for original_node, step in self._report_steps:
  245. report_steps_by_node[node_map[original_node]].append(step)
  246. grouped_by_node = TaskGroup()
  247. for node, tasks in viewitems(tasks_by_node):
  248. report_steps = report_steps_by_node[node]
  249. node_inits, node_exits = get_setup_nets(
  250. TaskGroup.LOCAL_SETUP,
  251. [t.get_step() for t in tasks] + report_steps,
  252. self)
  253. # shortcut for single task with no queue
  254. steps = report_steps
  255. outputs = []
  256. grouped_workspace_type = WorkspaceType.PRIVATE
  257. for task in tasks:
  258. step = task.get_step()
  259. step.SetCreateWorkspace(
  260. task.workspace_type() == WorkspaceType.PRIVATE)
  261. if step is not None:
  262. steps.append(step)
  263. outputs += task.outputs()
  264. # If any of the tasks in the node uses the global workspace,
  265. # then set the grouped task to use the global workspace as well
  266. if task.workspace_type() == WorkspaceType.GLOBAL:
  267. grouped_workspace_type = WorkspaceType.GLOBAL
  268. if len(steps) == 0:
  269. steps.append(core.execution_step('empty', []))
  270. if len(steps) == 1:
  271. step = steps[0]
  272. else:
  273. step = core.execution_step(
  274. '%s:body' % node, steps, concurrent_substeps=True)
  275. if len(node_inits) > 0 or len(node_exits) > 0:
  276. steps = []
  277. if len(node_inits) > 0:
  278. steps.append(
  279. core.execution_step('%s:init' % node, node_inits))
  280. steps.append(step)
  281. if len(node_exits) > 0:
  282. steps.append(
  283. core.execution_step('%s:exit' % node, node_exits))
  284. step = core.execution_step(node, steps)
  285. Task(
  286. node=node, step=step, outputs=outputs,
  287. name='grouped_by_node',
  288. group=grouped_by_node, workspace_type=grouped_workspace_type)
  289. self._tasks_by_node = (grouped_by_node, node_map)
  290. return grouped_by_node
  291. def to_task(self, node=None):
  292. node = str(Node.current(node))
  293. tasks = self.tasks_by_node(lambda x: node).tasks()
  294. if len(tasks) == 0:
  295. return Task()
  296. return tasks[0]
  297. def workspace_type(self):
  298. return self._workspace_type
  299. def __repr__(self):
  300. return "TaskGroup(tasks={}, workspace_type={}, remote_nets={})".format(
  301. self._tasks + self._tasks_to_add,
  302. self.workspace_type(),
  303. self.remote_nets())
  304. class TaskOutput(object):
  305. """
  306. Represents the output of a task. An output can be a blob,
  307. a list of blob, or a record.
  308. """
  309. def __init__(self, names):
  310. self._schema = None
  311. self._is_scalar = False
  312. if isinstance(names, Field):
  313. self._schema = names
  314. names = self._schema.field_blobs()
  315. self._is_scalar = type(names) not in (tuple, list)
  316. if self._is_scalar:
  317. names = [names]
  318. self.names = names
  319. self._values = None
  320. def set(self, values, _fetch_func=None):
  321. assert len(values) == len(self.names)
  322. self._values = values
  323. self._fetch_func = _fetch_func
  324. def get(self):
  325. assert self._values is not None, 'Output value not set yet.'
  326. if self._is_scalar:
  327. return self._values[0]
  328. elif self._schema:
  329. return from_blob_list(self._schema, self._values)
  330. else:
  331. return self._values
  332. def fetch(self):
  333. assert self._fetch_func is not None, (
  334. 'Cannot fetch value for this output.')
  335. fetched_vals = [self._fetch_func(v) for v in self._values]
  336. if self._is_scalar:
  337. return fetched_vals[0]
  338. elif self._schema:
  339. return from_blob_list(self._schema, fetched_vals)
  340. else:
  341. return fetched_vals
  342. def __repr__(self):
  343. return "TaskOutput(names={}, values={})".format(self.names, self._values)
  344. def final_output(blob_or_record):
  345. """
  346. Adds an output to the current Task, or if no task is active,
  347. create a dummy task that returns the given blob or record
  348. to the client. This will return the value of the blob or record when
  349. the last task of the TaskGroup for a given node finishes.
  350. """
  351. cur_task = Task.current(required=False) or Task()
  352. return cur_task.add_output(blob_or_record)
  353. class TaskOutputList(object):
  354. """ Keeps a list of outputs for a task """
  355. def __init__(self, outputs=None):
  356. self.outputs = outputs or []
  357. def names(self):
  358. """
  359. Retrive the output names.
  360. TODO(azzolini): make this schema-based.
  361. """
  362. names = []
  363. for o in self.outputs:
  364. names += o.names
  365. return names
  366. def set_values(self, values, _fetch_func=None):
  367. offset = 0
  368. for o in self.outputs:
  369. num = len(o.names)
  370. o.set(values[offset:offset + num], _fetch_func)
  371. offset += num
  372. assert offset == len(values), 'Wrong number of output values.'
  373. def __repr__(self):
  374. return "TaskOutputList(outputs={})".format(self.outputs)
  375. class Task(context.Managed):
  376. """
  377. A Task is composed of an execution step and zero or more outputs.
  378. Tasks are executed in the context of a TaskGroup, which, in turn, can
  379. be run by a Session.
  380. Task outputs are fetched by the session at the end of the run.
  381. The recommended way of creating a task is by using `net_builder.ops`.
  382. Example:
  383. from net_builder import ops
  384. with Node('trainer'), Task(name='my_task', num_instances=2):
  385. with ops.task_init():
  386. globl = ops.Const(0)
  387. with ops.task_instance_init():
  388. local = ops.Const(0)
  389. with ops.loop(100):
  390. ops.Copy(globl, local)
  391. with ops.task_instance_exit():
  392. ops.Add([globl, local], [globl])
  393. with ops.task_exit():
  394. ops.Mul([globl, globl], [globl])
  395. The task above will create 2 instances that will run in parallel.
  396. Each instance will copy `local` to `globl` 100 times, Then Add `local`
  397. to `globl` once. The `Mul` will only execute once, after all the instances
  398. of the task have finished.
  399. """
  400. # TASK_SETUP runs once per task, before/after all
  401. # concurrent task instances start/finish.
  402. TASK_SETUP = 'task_setup'
  403. # Setup will run once for each instance of the task.
  404. TASK_INSTANCE_SETUP = 'task_instance_setup'
  405. REPORT_STEP = 'report_step'
  406. _global_names_used = set()
  407. @staticmethod
  408. def _get_next_name(node, group, name):
  409. basename = str(node) + '/' + str(name)
  410. names_used = (
  411. Task._global_names_used
  412. if group is None else
  413. set(t.name for t in group._tasks_to_add))
  414. cur_name = basename
  415. i = 0
  416. while cur_name in names_used:
  417. i += 1
  418. cur_name = '%s:%d' % (basename, i)
  419. return cur_name
  420. def __init__(
  421. self, step=None, outputs=None,
  422. workspace_type=None, group=None, node=None, name=None,
  423. num_instances=None):
  424. """
  425. Instantiate a Task and add it to the current TaskGroup and Node.
  426. Args:
  427. step: If provided, this task will run this ExecutionStep.
  428. outputs: If provided, the task will return the provided outputs
  429. to the client at completion time.
  430. node: If provided, force task execution on the given node.
  431. name: Name of the Task.
  432. num_instances: If provided, this task will be cloned num_instances
  433. times at runtime, and all instances will run
  434. concurrently.
  435. """
  436. if not name and isinstance(step, core.ExecutionStep):
  437. name = step.Proto().name
  438. if not name:
  439. name = 'task'
  440. # register this node name with active context
  441. self.node = str(Node.current(None if node is None else Node(node)))
  442. self.group = TaskGroup.current(group, required=False)
  443. self.name = Task._get_next_name(self.node, self.group, name)
  444. # may need to be temporarily removed later if Task used as a context
  445. if self.group is not None:
  446. self.group._tasks_to_add.append(self)
  447. self._already_used = False
  448. self._step = None
  449. self._step_with_setup = None
  450. self._outputs = []
  451. if step is not None:
  452. self.set_step(step)
  453. if outputs is not None:
  454. self.add_outputs(outputs)
  455. self._pipeline = None
  456. self._is_pipeline_context = False
  457. self._workspace_type = workspace_type
  458. self._report_net = None
  459. self._num_instances = num_instances
  460. def __enter__(self):
  461. super(Task, self).__enter__()
  462. # temporarily remove from _tasks_to_add to ensure correct order
  463. if self.group is not None:
  464. self.group._tasks_to_add.remove(self)
  465. self._assert_not_used()
  466. assert self._step is None, 'This Task already has an execution step.'
  467. from caffe2.python import net_builder
  468. self._net_builder = net_builder.NetBuilder(_fullname=self.name)
  469. self._net_builder.__enter__()
  470. return self
  471. def __exit__(self, type, value, traceback):
  472. super(Task, self).__exit__(type, value, traceback)
  473. self._net_builder.__exit__(type, value, traceback)
  474. if type is None:
  475. self.set_step(self._net_builder)
  476. if self.group is not None:
  477. self.group._tasks_to_add.append(self)
  478. self._net_builder = None
  479. def workspace_type(self):
  480. return self._workspace_type
  481. def _assert_not_used(self):
  482. assert not self._already_used, (
  483. 'Cannot modify task since it is already been used.')
  484. def add_output(self, output):
  485. self._assert_not_used()
  486. output = (
  487. output if isinstance(output, TaskOutput) else TaskOutput(output))
  488. self._outputs.append(output)
  489. return output
  490. def add_outputs(self, outputs):
  491. self._assert_not_used()
  492. if type(outputs) not in (list, tuple):
  493. return self.add_output(outputs)
  494. else:
  495. return [self.add_output(output) for output in outputs]
  496. def set_step(self, step):
  497. self._assert_not_used()
  498. self._step = core.to_execution_step(step)
  499. def get_step(self):
  500. if self._step_with_setup is not None:
  501. return self._step_with_setup
  502. if self._step is None:
  503. self._step_with_setup = core.execution_step(self.name, [])
  504. return self._step_with_setup
  505. report_steps = [
  506. s
  507. for s in self._step.get_all_attributes(Task.REPORT_STEP)
  508. if not hasattr(s, '_report_step_used')
  509. ]
  510. for step in report_steps:
  511. step._report_step_used = True
  512. if not step.Proto().run_every_ms:
  513. step.RunEveryMillis(1000)
  514. task_init_nets, task_exit_nets = get_setup_nets(
  515. Task.TASK_SETUP, [self._step] + report_steps, self)
  516. instance_init_nets, instance_exit_nets = get_setup_nets(
  517. Task.TASK_INSTANCE_SETUP, [self._step] + report_steps, self)
  518. if len(self._outputs) == 0:
  519. output_net = core.Net('%s:output' % self.name)
  520. self.add_output(output_net.ConstantFill(
  521. [], 1, dtype=core.DataType.INT32, value=0))
  522. task_exit_nets.append(output_net)
  523. # Add instance-level report steps
  524. body = self._step if not report_steps else core.execution_step(
  525. '%s:body' % self.name, report_steps + [self._step])
  526. # Enclose with instance-level (thread-local) setup nets
  527. step_with_instance_setup = add_setup_steps(
  528. body, instance_init_nets, instance_exit_nets,
  529. self.name + ':instance')
  530. # Set up runtime concurrent instances
  531. if self._num_instances and self._num_instances > 1:
  532. step_with_instance_setup.SetCreateWorkspace(True)
  533. step_with_instance_setup = core.execution_step(
  534. '%s:parallel',
  535. [step_with_instance_setup],
  536. num_concurrent_instances=self._num_instances)
  537. # Enclose with task-level setup nets
  538. self._step_with_setup = add_setup_steps(
  539. step_with_instance_setup, task_init_nets, task_exit_nets, self.name)
  540. return self._step_with_setup
  541. def output_list(self):
  542. return TaskOutputList(self._outputs)
  543. def outputs(self):
  544. return self._outputs
  545. def _notify_used(self):
  546. self.get_step()
  547. self._already_used = True
  548. def __repr__(self):
  549. return "Task(name={}, node={}, outputs={})".format(
  550. self.name, self.node, self.outputs())
  551. class SetupNets(object):
  552. """
  553. Allow to register a list of nets to be run at initialization
  554. and finalization of Tasks or TaskGroups.
  555. For example, let's say you have the following:
  556. init_net = core.Net('init')
  557. my_val = init_net.ConstantFill([], 'my_val', value=0)
  558. net = core.Net('counter')
  559. net.Add([my_val, net.Const(1),], [my_val])
  560. with TaskGroup() as task_group:
  561. with Node('trainer'):
  562. my_task = Task(step=[net])
  563. In order to have `init_net` run once before `net` runs for the
  564. first time, you can do one of the following:
  565. net.add_attribute(Task.TASK_SETUP, SetupNets([init_net]))
  566. or
  567. net.add_attribute(TaskGroup.LOCAL_SETUP, SetupNets([init_net]))
  568. - With Task.TASK_SETUP, init_net will run once at my_task startup.
  569. - With TaskGroup.LOCAL_SETUP, init_net will run once on node 'trainer',
  570. before any task of the task group is run on that node.
  571. The same SetupNets object can be added to multiple nets. It will only
  572. run once per Task/TaskGroup run.
  573. """
  574. def __init__(self, init_nets=None, exit_nets=None):
  575. self.init_nets = init_nets
  576. self.exit_nets = exit_nets
  577. def setup(self, init_net):
  578. return self.init_nets
  579. def exit(self, exit_net):
  580. return self.exit_nets
  581. def __repr__(self):
  582. return "SetupNets(init_nets={}, exit_nets={})".format(
  583. self.init_nets, self.exit_nets)