Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id 18D49200D1B for ; Thu, 28 Sep 2017 04:57:08 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id 176871609EB; Thu, 28 Sep 2017 02:57:08 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 545221609CA for ; Thu, 28 Sep 2017 04:57:07 +0200 (CEST) Received: (qmail 3524 invoked by uid 500); 28 Sep 2017 02:57:05 -0000 Mailing-List: contact user-help@hive.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hive.apache.org Delivered-To: mailing list user@hive.apache.org Received: (qmail 3515 invoked by uid 99); 28 Sep 2017 02:57:05 -0000 Received: from mail-relay.apache.org (HELO mail-relay.apache.org) (140.211.11.15) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 28 Sep 2017 02:57:05 +0000 Received: from [10.42.80.104] (outbound.hortonworks.com [192.175.27.2]) by mail-relay.apache.org (ASF Mail Server at mail-relay.apache.org) with ESMTPSA id 16EA51A0040 for ; Thu, 28 Sep 2017 02:57:04 +0000 (UTC) User-Agent: Microsoft-MacOutlook/f.26.0.170902 Date: Wed, 27 Sep 2017 19:56:59 -0700 Subject: Re: Hive query starts own session for LLAP From: Gopal Vijayaraghavan To: "user@hive.apache.org" Message-ID: <5EFCCE7A-8DCD-4BA1-9A04-649C27FF297F@hortonworks.com> Thread-Topic: Hive query starts own session for LLAP References: In-Reply-To: Mime-version: 1.0 Content-type: text/plain; charset="UTF-8" Content-transfer-encoding: 7bit archived-at: Thu, 28 Sep 2017 02:57:08 -0000 > Now we need an explanation of "map" -- can you supply it? The "map" mode runs all tasks with a TableScan operator inside LLAP instances and all other tasks in Tez YARN containers. This is the LLAP + Tez hybrid mode, which introduces some complexity in debugging a single query. The "only" mode is so far the best option since, the LlapDecider runs very late in the optimizer order the earlier optimizers need to hedge their bets on whether LLAP will finally be used for a vertex or not. The "only" mode sort of short-cuts that by assuring all optimizers that it is "LLAP or Bust!". Cheers, Gopal