/usr/lib/swipl/library/thread.pl
All Application Manual Name SummaryHelp

  • swipl
    • library
      • error.pl
      • debug.pl
      • apply.pl
      • lists.pl -- List Manipulation
      • broadcast.pl
      • shlib.pl -- Utility library for loading foreign objects (DLLs, shared objects)
      • option.pl -- Option list processing
      • thread_pool.pl -- Resource bounded thread management
      • gensym.pl
      • settings.pl -- Setting management
      • arithmetic.pl -- Extensible arithmetic
      • main.pl -- Provide entry point for scripts
      • readutil.pl -- Read utilities
      • operators.pl
      • pairs.pl -- Operations on key-value lists
      • prolog_source.pl -- Examine Prolog source-files
      • record.pl -- Access compound arguments by name
      • quasi_quotations.pl -- Define Quasi Quotation syntax
      • sandbox.pl
      • apply_macros.pl -- Goal expansion rules to avoid meta-calling
      • yall.pl -- Lambda expressions
      • assoc.pl -- Binary associations
      • prolog_format.pl -- Analyse format specifications
      • pure_input.pl -- Pure Input from files and streams
      • solution_sequences.pl
      • ordsets.pl -- Ordered set manipulation
      • random.pl -- Random numbers
      • base64.pl -- Base64 encoding and decoding
      • aggregate.pl -- Aggregation operators on backtrackable predicates
      • predicate_options.pl -- Access and analyse predicate options
      • csv.pl -- Process CSV (Comma-Separated Values) data
      • pprint.pl -- Pretty Print Prolog terms
      • atom.pl -- Operations on atoms
      • modules.pl -- Module utility predicates
      • occurs.pl -- Finding and counting sub-terms
      • prolog_xref.pl
      • prolog_colour.pl -- Prolog syntax colouring support.
      • lazy_lists.pl -- Lazy list handling
      • ugraphs.pl -- Graph manipulation library
      • url.pl -- Analysing and constructing URL
      • www_browser.pl -- Open a URL in the users browser
      • prolog_pack.pl -- A package manager for Prolog
      • git.pl -- Run GIT commands
      • utf8.pl -- UTF-8 encoding/decoding on lists of character codes.
      • quintus.pl -- Quintus compatibility
      • prolog_versions.pl -- Demand specific (Prolog) versions
      • prolog_wrap.pl -- Wrapping predicates
      • dialect.pl -- Support multiple Prolog dialects
      • date.pl -- Process dates and times
      • persistency.pl -- Provide persistent dynamic predicates
      • iostream.pl -- Utilities to deal with streams
      • prolog_code.pl -- Utilities for reasoning about code
      • strings.pl -- String utilities
      • dif.pl -- The dif/2 constraint
      • edinburgh.pl -- Some traditional Edinburgh predicates
      • terms.pl
      • ansi_term.pl
      • threadutil.pl -- Interactive thread utilities
      • prolog_stack.pl -- Examine the Prolog stack
      • prolog_clause.pl
      • prolog_breakpoints.pl -- Manage Prolog break-points
      • wfs.pl -- Well Founded Semantics interface
      • sort.pl
      • dicts.pl -- Dict utilities
      • varnumbers.pl -- Utilities for numbered terms
      • base32.pl
      • charsio.pl -- I/O on Lists of Character Codes
      • codesio.pl -- I/O on Lists of Character Codes
      • coinduction.pl -- Co-Logic Programming
      • heaps.pl
      • rbtrees.pl -- Red black trees
      • statistics.pl -- Get information about resource usage
      • when.pl -- Conditional coroutining
      • backcomp.pl -- Backward compatibility
      • ctypes.pl -- Character code classification
      • tableutil.pl
      • listing.pl
      • exceptions.pl -- Exception classification
      • intercept.pl
      • help.pl
      • edit.pl -- Editor interface
      • qpforeign.pl -- Quintus compatible foreign loader
      • prolog_profile.pl -- Execution profiler
      • streams.pl
      • make.pl
      • prolog_jiti.pl
      • portray_text.pl
      • prolog_coverage.pl
      • fastrw.pl
      • prolog_debug.pl -- User level debugging tools
      • thread.pl -- High level thread primitives
        • concurrent/3
        • concurrent_forall/2
        • concurrent_forall/3
        • concurrent_and/2
        • concurrent_and/3
        • concurrent_maplist/2
        • concurrent_maplist/3
        • concurrent_maplist/4
        • first_solution/3
        • call_in_thread/2
        • call_in_thread/3
      • prolog_codewalk.pl
      • prolog_metainference.pl -- Infer meta-predicate properties
      • prolog_trace.pl -- Print access to predicates
      • system.pl -- System utilities
      • shell.pl -- Elementary shell commands
      • hashtable.pl -- Hash tables
      • check_installation.pl -- Check installation issues and features
      • oset.pl -- Ordered set manipulation
      • nb_set.pl
      • readln.pl
      • vm.pl -- SWI-Prolog Virtual Machine utilities
      • explain.pl -- Describe Prolog Terms
      • check.pl -- Consistency checking
      • increval.pl -- Incremental dynamic predicate modification
      • tables.pl
      • optparse.pl
      • macros.pl
      • files.pl
      • qsave.pl
      • zip.pl
      • prolog_deps.pl
      • writef.pl
      • tty.pl
      • prolog_config.pl
      • prolog_autoload.pl
      • prolog_history.pl
      • rwlocks.pl
      • nb_rbtrees.pl
 concurrent_forall(:Generate, :Action) is semidet
 concurrent_forall(:Generate, :Action, +Options) is semidet
True when Action is true for all solutions of Generate. This has the same semantics as forall/2, but the Action goals are executed in multiple threads. Notable a failing Action or a Action throwing an exception signals the calling thread which in turn aborts all workers and fails or re-throws the generated error. Options:
threads(+Count)
Number of threads to use. The default is determined by the Prolog flag cpu_count.
To be done
- Ideally we would grow the set of workers dynamically, similar to dynamic scheduling of HTTP worker threads. This would avoid creating threads that are never used if Generate is too slow or does not provide enough answers and would further raise the number of threads if Action is I/O bound rather than CPU bound.