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 07818200B21 for ; Thu, 12 May 2016 02:20:59 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id 062D5160A18; Thu, 12 May 2016 00:20:59 +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 4DDD0160A17 for ; Thu, 12 May 2016 02:20:58 +0200 (CEST) Received: (qmail 3042 invoked by uid 500); 12 May 2016 00:20:57 -0000 Mailing-List: contact dev-help@impala.incubator.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@impala.incubator.apache.org Delivered-To: mailing list dev@impala.incubator.apache.org Received: (qmail 3028 invoked by uid 99); 12 May 2016 00:20:57 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd3-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 12 May 2016 00:20:57 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd3-us-west.apache.org (ASF Mail Server at spamd3-us-west.apache.org) with ESMTP id C1B0E1805A9 for ; Thu, 12 May 2016 00:20:56 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd3-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: 0.362 X-Spam-Level: X-Spam-Status: No, score=0.362 tagged_above=-999 required=6.31 tests=[RDNS_DYNAMIC=0.363, SPF_PASS=-0.001] autolearn=disabled Received: from mx1-lw-eu.apache.org ([10.40.0.8]) by localhost (spamd3-us-west.apache.org [10.40.0.10]) (amavisd-new, port 10024) with ESMTP id 7OGzoXNyEzQr for ; Thu, 12 May 2016 00:20:54 +0000 (UTC) Received: from ip-10-146-233-104.ec2.internal (ec2-75-101-130-251.compute-1.amazonaws.com [75.101.130.251]) by mx1-lw-eu.apache.org (ASF Mail Server at mx1-lw-eu.apache.org) with ESMTPS id DE27A5F23C for ; Thu, 12 May 2016 00:20:53 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by ip-10-146-233-104.ec2.internal (8.14.4/8.14.4) with ESMTP id u4C0KqNP009102; Thu, 12 May 2016 00:20:52 GMT Message-Id: <201605120020.u4C0KqNP009102@ip-10-146-233-104.ec2.internal> Date: Thu, 12 May 2016 00:20:52 +0000 From: "Lars Volker (Code Review)" To: impala-cr@cloudera.com, dev@impala.incubator.apache.org Reply-To: lv@cloudera.com X-Gerrit-MessageType: newpatchset Subject: =?UTF-8?Q?[Impala-CR](cdh5-trunk)_IMPALA-3019:_Fix_unnecessary_resets_of_iterator=0A?= X-Gerrit-Change-Id: I831d485b46c7d9460fb014a302a26864b6bd573e X-Gerrit-ChangeURL: X-Gerrit-Commit: c3d1fc9191b0bb30f47c5c8229b9a0d4c129b182 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Content-Disposition: inline User-Agent: Gerrit/2.10-rc0 archived-at: Thu, 12 May 2016 00:20:59 -0000 Lars Volker has uploaded a new patch set (#2). Change subject: IMPALA-3019: Fix unnecessary resets of iterator ...................................................................... IMPALA-3019: Fix unnecessary resets of iterator In order to perform round-robin backend selection, the simple scheduler uses an iterator to the next backend entry to be selected. This iterator needs to be reset whenever it is invalidated by changes to the underlying map. The current behavior resets the pointer on every message of the statestored, even if the message was empty and thus did not result in any changes to the map. After every reset of the iterator round-robin selection starts from the first backend in the scheduler's backend map. As the statestored sends empty keepalive messages every couple of seconds, this effectively limits scheduling of remote reads to only a few backends. This change introduces a check to prevent those unnecessary iterator resets, which will spread remote reads more evenly over all backends. Change-Id: I831d485b46c7d9460fb014a302a26864b6bd573e Reviewed-on: http://gerrit.cloudera.org:8080/2330 Reviewed-by: Lars Volker Tested-by: Internal Jenkins (cherry picked from commit fc743d69f8ed671cebaca89f41f5373e326ffee5) --- M be/src/scheduling/simple-scheduler.cc 1 file changed, 6 insertions(+), 1 deletion(-) git pull ssh://gerrit.cloudera.org:29418/Impala refs/changes/31/3031/2 -- To view, visit http://gerrit.cloudera.org:8080/3031 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: newpatchset Gerrit-Change-Id: I831d485b46c7d9460fb014a302a26864b6bd573e Gerrit-PatchSet: 2 Gerrit-Project: Impala Gerrit-Branch: cdh5-trunk Gerrit-Owner: Lars Volker Gerrit-Reviewer: Internal Jenkins