j fD@svdZdZddlZddlZddlmZddlZddlmZddlZddlm Z ddl m Z ddl Z ddl Z e jZdad d Zd ZGd d d eZGdddeZGdddeZddZddZddZdadaddZGdddeZGdddejZ ej!edS)a* Implements ProcessPoolExecutor. The follow diagram and text describe the data-flow through the system: |======================= In-process =====================|== Out-of-process ==| +----------+ +----------+ +--------+ +-----------+ +---------+ | | => | Work Ids | => | | => | Call Q | => | | | | +----------+ | | +-----------+ | | | | | ... | | | | ... | | | | | | 6 | | | | 5, call() | | | | | | 7 | | | | ... | | | | Process | | ... | | Local | +-----------+ | Process | | Pool | +----------+ | Worker | | #1..n | | Executor | | Thread | | | | | +----------- + | | +-----------+ | | | | <=> | Work Items | <=> | | <= | Result Q | <= | | | | +------------+ | | +-----------+ | | | | | 6: call() | | | | ... | | | | | | future | | | | 4, result | | | | | | ... | | | | 3, except | | | +----------+ +------------+ +--------+ +-----------+ +---------+ Executor.submit() called: - creates a uniquely numbered _WorkItem and adds it to the "Work Items" dict - adds the id of the _WorkItem to the "Work Ids" queue Local worker thread: - reads work ids from the "Work Ids" queue and looks up the corresponding WorkItem from the "Work Items" dict: if the work item has been cancelled then it is simply removed from the dict, otherwise it is repackaged as a _CallItem and put in the "Call Q". New _CallItems are put in the "Call Q" until "Call Q" is full. NOTE: the size of the "Call Q" is kept small because calls placed in the "Call Q" can no longer be cancelled with Future.cancel(). - reads _ResultItems from "Result Q", updates the future stored in the "Work Items" dict and deletes the dict entry Process #1..n: - reads _CallItems from "Call Q", executes the calls, and puts the resulting _ResultItems in "Result Q" z"Brian Quinlan (brian@sweetapp.com)N)_base)Full) SimpleQueue)waitFcCsadattj}x!|D]\}}|jdqWx|D]\}}|jqCWdS)NT) _shutdownlist_threads_queuesitemsputjoin)r tqr?/opt/alt/python34/lib64/python3.4/concurrent/futures/process.py _python_exitLs rc@seZdZddZdS) _WorkItemcCs(||_||_||_||_dS)N)futurefnargskwargs)selfrrrrrrr__init__\s   z_WorkItem.__init__N)__name__ __module__ __qualname__rrrrrr[s rc@s"eZdZddddZdS) _ResultItemNcCs||_||_||_dS)N)work_id exceptionresult)rrrrrrrrcs  z_ResultItem.__init__)rrrrrrrrrbs rc@seZdZddZdS) _CallItemcCs(||_||_||_||_dS)N)rrrr)rrrrrrrrris   z_CallItem.__init__N)rrrrrrrrr hs r cCsx|jdd}|dkr8|jtjdSy|j|j|j}WnAtk r}z!|jt|j d|WYdd}~XqX|jt|j d|qWdS)aEvaluates calls from call_queue and places the results in result_queue. This worker is run in a separate process. Args: call_queue: A multiprocessing.Queue of _CallItems that will be read and evaluated by the worker. result_queue: A multiprocessing.Queue of _ResultItems that will written to by the worker. shutdown: A multiprocessing.Event that will be set as a signal to the worker that it should exit when call_queue is empty. blockTNrr) getr osgetpidrrr BaseExceptionrr) call_queue result_queueZ call_itemrerrr_process_workeros  r*cCsx|jrdSy|jdd}Wntjk rDdSYqX||}|jjr|jt||j|j |j ddq||=qqWdS)aMFills call_queue with _WorkItems from pending_work_items. This function never blocks. Args: pending_work_items: A dict mapping work ids to _WorkItems e.g. {5: <_WorkItem...>, 6: <_WorkItem...>, ...} work_ids: A queue.Queue of work ids e.g. Queue([5, 6, ...]). Work ids are consumed and the corresponding _WorkItems from pending_work_items are transformed into _CallItems and put in call_queue. call_queue: A multiprocessing.Queue that will be filled with _CallItems derived from _WorkItems. Nr!FT) fullr"queueZEmptyrZset_running_or_notify_cancelr r rrr)pending_work_itemsZwork_idsr&r work_itemrrr_add_call_item_to_queues       r/c sdfdd}fdd}|j}xt||ddjD} t|g| } || kr|j} n|dk rd_d_dnx3|jD]%\} } | jj t d ~ qW|j xjD]}|j q W|dSt | trhj| }|js|dSnh| dk r|j| jd} | dk r| jr| jj | jn| jj| j~ qn||ry|s|dSWqtk r YqXndq9WdS) aManages the communication between this process and the worker processes. This function is run in a local thread. Args: executor_reference: A weakref.ref to the ProcessPoolExecutor that owns this thread. Used to determine if the ProcessPoolExecutor has been garbage collected and that this function can exit. process: A list of the multiprocessing.Process instances used as workers. pending_work_items: A dict mapping work ids to _WorkItems e.g. {5: <_WorkItem...>, 6: <_WorkItem...>, ...} work_ids_queue: A queue.Queue of work ids e.g. Queue([5, 6, ...]). call_queue: A multiprocessing.Queue that will be filled with _CallItems derived from _WorkItems for processing by the process workers. result_queue: A multiprocessing.Queue of _ResultItems generated by the process workers. NcstpdkpjS)N)r_shutdown_threadr)executorrr shutting_downsz/_queue_management_worker..shutting_downcsutddjD}x$td|D]}jdq/WjxjD]}|jq]WdS)Ncss|]}|jVqdS)N)Zis_alive).0prrr szD_queue_management_worker..shutdown_worker..r)sumvaluesrangeZ put_nowaitcloser )Znb_children_aliveir4)r& processesrrshutdown_workers  z1_queue_management_worker..shutdown_workercSsg|]}|jqSr)sentinel)r3r4rrr s z,_queue_management_worker..Tz^A process in the process pool was terminated abruptly while the future was running or pending.)Z_readerr/r7rZrecv_brokenr0r rZ set_exceptionBrokenProcessPoolclearZ terminate isinstanceintpopr rrZ set_resultrr)Zexecutor_referencer;r-Zwork_ids_queuer&r'r2r<readerZ sentinelsZreadyZ result_itemrr.r4r)r&r1r;r_queue_management_workersb                  rFc Cstrtrttqndaytjd}Wnttfk rUdSYnX|dkrfdS|dkrvdSd|attdS)NTSC_SEM_NSEMS_MAXrz@system provides too few semaphores (%d available, 256 necessary))_system_limits_checked_system_limitedNotImplementedErrorr#sysconfAttributeError ValueError)Z nsems_maxrrr_check_system_limits%s    rPc@seZdZdZdS)r@zy Raised when a process in a ProcessPoolExecutor terminated abruptly while a future was in the running state. N)rrr__doc__rrrrr@<s r@c@sveZdZdddZddZddZdd Zejjj e_ d d d Z ejj j e _ dS) ProcessPoolExecutorNcCst|dkr+tjp"d|_n ||_tj|jt|_d|j_t |_ t j|_ d|_ i|_d|_tj|_d|_d|_i|_dS)a/Initializes a new ProcessPoolExecutor instance. Args: max_workers: The maximum number of processes that can be used to execute the given calls. If None or not given then as many worker processes will be created as the machine has processors. NrTFr)rPr# cpu_count _max_workersmultiprocessingZQueueEXTRA_QUEUED_CALLS _call_queueZ _ignore_epiper _result_queuer, _work_ids_queue_management_thread _processesr0 threadingZLock_shutdown_lockr? _queue_count_pending_work_items)rZ max_workersrrrrDs            zProcessPoolExecutor.__init__c Cs|jdd}|jdkr|jtjdtdtj|||j|j |j |j |jf|_d|j_ |jj |jt|j.weakref_cbtargetrT)rXrZ_adjust_process_countr\ZThreadrFweakrefrefr[r_rYrWZdaemonstartr)rrarrr_start_queue_management_threadis    z2ProcessPoolExecutor._start_queue_management_threadcCshxatt|j|jD]D}tjdtd|j|jf}|j ||j|j ,s6          % s h