Return-Path: X-Original-To: apmail-hive-issues-archive@minotaur.apache.org Delivered-To: apmail-hive-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id DFE3210557 for ; Tue, 3 Mar 2015 19:05:04 +0000 (UTC) Received: (qmail 33912 invoked by uid 500); 3 Mar 2015 19:05:04 -0000 Delivered-To: apmail-hive-issues-archive@hive.apache.org Received: (qmail 33895 invoked by uid 500); 3 Mar 2015 19:05:04 -0000 Mailing-List: contact issues-help@hive.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@hive.apache.org Delivered-To: mailing list issues@hive.apache.org Received: (qmail 33885 invoked by uid 99); 3 Mar 2015 19:05:04 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 03 Mar 2015 19:05:04 +0000 Date: Tue, 3 Mar 2015 19:05:04 +0000 (UTC) From: "Pengcheng Xiong (JIRA)" To: issues@hive.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (HIVE-6617) Reduce ambiguity in grammar MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/HIVE-6617?page=3Dcom.atlassian= .jira.plugin.system.issuetabpanels:all-tabpanel ] Pengcheng Xiong updated HIVE-6617: ---------------------------------- Attachment: parser.png Performance comparison between the old parser and the proposed new parser (= in this jira) I directly measured the parsing time of an Hive query, which is defined as = the time that ANTLR takes from accepting the string to outputting the AST. = I parsed 19025 queries in 1888 files in client positive q tests of CliDrive= r with my laptop. (Darwin Kernel Version 13.2.0, Intel(R) Core(TM) i7-4850H= Q CPU @ 2.30GHz, Primary memory available: 16.00 gigabytes)=20 I compared 3 cases, default (Hive default parser), TRUE (Proposed new parse= r with a configuration to support SQL reserved keywords), FALSE (Proposed= new parser with a configuration not to support SQL reserved keywords for b= ackward compatibility). The CDF is shown as attached. Please note that Y-ax= is is measured in nano seconds (10=E2=88=929). It seems that=20 (1) There is no significant difference among the 3, which proves that there= is no significant performance penalty for the new parser. (2) It only takes 0.4ms to finish parsing for half of the queries. And the = longest one, less than 2ms for all of them.=20 > Reduce ambiguity in grammar > --------------------------- > > Key: HIVE-6617 > URL: https://issues.apache.org/jira/browse/HIVE-6617 > Project: Hive > Issue Type: Task > Reporter: Ashutosh Chauhan > Assignee: Pengcheng Xiong > Attachments: HIVE-6617.01.patch, HIVE-6617.02.patch, HIVE-6617.03= .patch, HIVE-6617.04.patch, HIVE-6617.05.patch, HIVE-6617.06.patch, HIVE-66= 17.07.patch, HIVE-6617.08.patch, HIVE-6617.09.patch, HIVE-6617.10.patch, HI= VE-6617.11.patch, HIVE-6617.12.patch, HIVE-6617.13.patch, HIVE-6617.14.patc= h, HIVE-6617.15.patch, HIVE-6617.16.patch, HIVE-6617.17.patch, HIVE-6617.18= .patch, HIVE-6617.19.patch, HIVE-6617.20.patch, HIVE-6617.21.patch, parser.= png > > > CLEAR LIBRARY CACHE > As of today, antlr reports 214 warnings. Need to bring down this number, = ideally to 0. -- This message was sent by Atlassian JIRA (v6.3.4#6332)