From issues-return-165699-archive-asf-public=cust-asf.ponee.io@hive.apache.org Sat Aug 31 15:02:02 2019 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [207.244.88.153]) by mx-eu-01.ponee.io (Postfix) with SMTP id 221BD18063F for ; Sat, 31 Aug 2019 17:02:02 +0200 (CEST) Received: (qmail 48945 invoked by uid 500); 31 Aug 2019 15:02:01 -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 48928 invoked by uid 99); 31 Aug 2019 15:02:01 -0000 Received: from mailrelay1-us-west.apache.org (HELO mailrelay1-us-west.apache.org) (209.188.14.139) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 31 Aug 2019 15:02:01 +0000 Received: from jira-he-de.apache.org (static.172.67.40.188.clients.your-server.de [188.40.67.172]) by mailrelay1-us-west.apache.org (ASF Mail Server at mailrelay1-us-west.apache.org) with ESMTP id AFB3DE3146 for ; Sat, 31 Aug 2019 15:02:00 +0000 (UTC) Received: from jira-he-de.apache.org (localhost.localdomain [127.0.0.1]) by jira-he-de.apache.org (ASF Mail Server at jira-he-de.apache.org) with ESMTP id 27984780C07 for ; Sat, 31 Aug 2019 15:02:00 +0000 (UTC) Date: Sat, 31 Aug 2019 15:02:00 +0000 (UTC) From: "Amruth S (Jira)" To: issues@hive.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (HIVE-22165) Synchronisation introduced by HIVE-14296 on SessionManager.closeSession introduces high latency in a busy hive server 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-22165?page=3Dcom.atlassia= n.jira.plugin.system.issuetabpanels:all-tabpanel ] Amruth S updated HIVE-22165: ---------------------------- Description:=20 HIVE-14296 introduces this [commit|https://github.com/apache/hive/commit/47= 7a47d3b4b9e3da3c22465217c2024588f7f000]=C2=A0which adds synchronization to = SessionManager.closeSession. And it looks like it is used only for logging purposes. In a busy hive server where 5-10 sessions are created closed every second, = an increase in latency of any other downstream services (Zk, HDFS) causes a= queuing effect (lot of threads getting blocked on SessionManager.closeSess= ion) creating an induced latency of 3-5 minutes at times for just closing t= he session.=C2=A0 Since the gauge (MetricsConstant.HS2_OPEN_SESSIONS) is already tracking the= open session counts, the synchronization (along with the additional loggin= g) can be removed. was: HIVE-14296 introduces this [commit|https://github.com/apache/hive/commit/47= 7a47d3b4b9e3da3c22465217c2024588f7f000]=C2=A0which adds synchronization to = SessionManager.closeSession. And it looks like it is used only for logging purposes. In a busy hive server where 5-10 sessions are created closed every second, = a increase in latency of any other downstream services (Zk, HDFS) causes a = queuing effect (lot of threads getting blocked on SessionManager.closeSessi= on) creating an induced latency of 3-5 minutes at times for just closing th= e session.=C2=A0 Since the gauge (MetricsConstant.HS2_OPEN_SESSIONS) is already tracking the= open session counts, the synchronization (along with the additional loggin= g) can be removed. > Synchronisation introduced by HIVE-14296 on SessionManager.closeSession i= ntroduces high latency in a busy hive server > -------------------------------------------------------------------------= -------------------------------------------- > > Key: HIVE-22165 > URL: https://issues.apache.org/jira/browse/HIVE-22165 > Project: Hive > Issue Type: Bug > Components: HiveServer2 > Affects Versions: 2.1.0, 2.3.2 > Reporter: Amruth S > Priority: Major > > HIVE-14296 introduces this [commit|https://github.com/apache/hive/commit/= 477a47d3b4b9e3da3c22465217c2024588f7f000]=C2=A0which adds synchronization t= o SessionManager.closeSession. > And it looks like it is used only for logging purposes. > In a busy hive server where 5-10 sessions are created closed every second= , an increase in latency of any other downstream services (Zk, HDFS) causes= a queuing effect (lot of threads getting blocked on SessionManager.closeSe= ssion) creating an induced latency of 3-5 minutes at times for just closing= the session.=C2=A0 > Since the gauge (MetricsConstant.HS2_OPEN_SESSIONS) is already tracking t= he open session counts, the synchronization (along with the additional logg= ing) can be removed. -- This message was sent by Atlassian Jira (v8.3.2#803003)