docsim.py 文件源码

def query_shards(self, query):
        """
        Return the result of applying shard[query] for each shard in self.shards,
        as a sequence.

        If PARALLEL_SHARDS is set, the shards are queried in parallel, using
        the multiprocessing module.
        """
        args = zip([query] * len(self.shards), self.shards)
        if PARALLEL_SHARDS and PARALLEL_SHARDS > 1:
            logger.debug("spawning %i query processes" % PARALLEL_SHARDS)
            pool = multiprocessing.Pool(PARALLEL_SHARDS)
            result = pool.imap(query_shard, args, chunksize=1 + len(args) / PARALLEL_SHARDS)
        else:
            # serial processing, one shard after another
            pool = None
            result = imap(query_shard, args)
        return pool, result