iXc@s!dZddlZddlmZddlZddlZddlZddlZddl Z dZ ej Z e adZdZdefdYZd efd YZd efd YZd ZdZdZe adadZdejfdYZejedS(s+ 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 "Request Q" iN(t_bases"Brian Quinlan (brian@sweetapp.com)cCsstatrttjnd}x!|D]\}}|jdq+Wx$|D]\}}|jtj qOWdS(N(( tTruet _shutdownt_threads_queuestlisttitemstputtNonetjointsystmaxint(Rtttq((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt _python_exitIs it _WorkItemcBseZdZRS(cCs(||_||_||_||_dS(N(tfuturetfntargstkwargs(tselfRRRR((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt__init__Ys   (t__name__t __module__R(((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyRXst _ResultItemcBseZdddZRS(cCs||_||_||_dS(N(twork_idt exceptiontresult(RRRR((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyR`s  N(RRRR(((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyR_st _CallItemcBseZdZRS(cCs(||_||_||_||_dS(N(RRRR(RRRRR((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyRfs   (RRR(((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyRescCsxtr|jdt}|dkr8|jddSy|j|j|j}Wn3tjd}|jt |j d|qX|jt |j d|qWdS(sEvaluates 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. tblockNiRR( RtgetRRRRRR texc_infoRR(t call_queuet result_queuet call_itemtrte((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt_process_workerls   cCsxtr|jrdSy|jdt}Wntjk rFdSX||}|jjr|jt ||j |j |j dtq||=qqWdS(sMFills 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( RtfullRtFalsetqueuetEmptyRtset_running_or_notify_cancelRRRRR(tpending_work_itemstwork_idsRRt work_item((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt_add_call_item_to_queues       c s&dgfd}xtr!t|||jdt}|dk r||j}||j=|jr|jj|jn|jj|j ~n|} t s| dks| j r|sx!dt |kr|qWx|D]} | j qWjdSn~ qWdS(sManages 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. ics!jddcd7/usr/lib/python2.7/site-packages/concurrent/futures/process.pytshutdown_one_processs RN(RR-RRRRRt set_exceptiont set_resultRRt_shutdown_threadtlenRtclose( texecutor_referencet processesR*twork_ids_queueRR R/t result_itemR,texecutortp((RR.s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt_queue_management_workers0          cCstrtrttqntayddl}|jd}Wnttfk r]dSX|dkrndS|dkr~dSd|attdS(NitSC_SEM_NSEMS_MAXis@system provides too few semaphores (%d available, 256 necessary)(t_system_limits_checkedt_system_limitedtNotImplementedErrorRtostsysconftAttributeErrort ValueError(R@t nsems_max((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt_check_system_limitss    tProcessPoolExecutorcBs_eZddZdZdZdZejjj e_ e dZ ejj j e _ RS(cCst|dkr%tj|_n$|dkr@tdn||_tj|jt|_tj|_ t j|_ d|_ t |_t|_tj|_d|_i|_dS(s/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. is"max_workers must be greater than 0N(RERtmultiprocessingt cpu_countt _max_workersRCtQueuetEXTRA_QUEUED_CALLSt _call_queuet _result_queueR't _work_idst_queue_management_threadtsett _processesR&R2t threadingtLockt_shutdown_lockt _queue_countt_pending_work_items(Rt max_workers((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyR s          c Cs|jd}|jdkrtjdtdtj|||j|j |j |j |jf|_t |j_ |jj|jt|j/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt weakref_cb0sttargetR(RMRORRRtThreadR;tweakreftrefRQRVRNRLRtdaemontstartR(RRY((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt_start_queue_management_thread-s   cCshxatt|j|jD]D}tjdtd|j|jf}|j |jj |qWdS(NRZR( trangeR3RQRIRGtProcessR$RLRMR_tadd(RRXR:((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt_adjust_process_count?s"  c Os|j|jr"tdntj}t||||}||j|j<|jj |j|jd7_|j j d|j |j |SWdQXdS(Ns*cannot schedule new futures after shutdowni(RTR2t RuntimeErrorRtFutureRRVRURNRRMRR`Rd(RRRRtftw((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pytsubmitHs     cCsy|jt|_WdQX|jrQ|jjd|rQ|jjtj qQnd|_d|_ d|_d|_ dS(N( RTRR2RORMRRRR R RLRQ(Rtwait((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pytshutdown[s     N( RRRRR`RdRiRtExecutort__doc__RRk(((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyRF s "   (Rmtatexittconcurrent.futuresRRJR'RGRRR\R t __author__tWeakKeyDictionaryRR&RR RKtobjectRRRR$R-R;R=RR>RERlRFtregister(((s>/usr/lib/python2.7/site-packages/concurrent/futures/process.pyt,s.          % B a