static L<Web> websMadeByProgram_parallel(S progID) {
  // TODO: clean up file handle in case of error
  IterableIterator<S> l = scanLog_iterator(progID, "webs-made.txt");
  S src = progID;
  
  int poolSize = numberOfCores(), queueSize = 20;
  NotifyingBlockingThreadPoolExecutor e = new(poolSize, queueSize, 15, TimeUnit.SECONDS);
 
  L<Pair<Web, Int>> webs;
  int i = 0;
  for (fS s : l) {
    ++i;
    final int _i = i;
    e.execute(r { pcall {
      SoftwareMadeWeb o = cast unstructure(s);
      Web web = o.web;
      if (web == null)
        web = (Web) unstructure(o.structure);
      if (web != null)
        webs.add(pair(web_intern(web_setSourceIfEmpty(web, src)), _i));
    }});
  }
  sortBySecondOfPairs_inPlace(webs);
  ret firstOfPairs(webs);
}