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 2C5AB200BBA for ; Sat, 22 Oct 2016 02:08:44 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id 2AD11160AE9; Sat, 22 Oct 2016 00:08:44 +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 731C8160AE8 for ; Sat, 22 Oct 2016 02:08:43 +0200 (CEST) Received: (qmail 29450 invoked by uid 500); 22 Oct 2016 00:08:42 -0000 Mailing-List: contact reviews-help@impala.incubator.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Delivered-To: mailing list reviews@impala.incubator.apache.org Received: (qmail 29439 invoked by uid 99); 22 Oct 2016 00:08:42 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd4-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 22 Oct 2016 00:08:42 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd4-us-west.apache.org (ASF Mail Server at spamd4-us-west.apache.org) with ESMTP id 06A75C0595 for ; Sat, 22 Oct 2016 00:08:42 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd4-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-us.apache.org ([10.40.0.8]) by localhost (spamd4-us-west.apache.org [10.40.0.11]) (amavisd-new, port 10024) with ESMTP id M-zEJNWMxraF for ; Sat, 22 Oct 2016 00:08:40 +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-us.apache.org (ASF Mail Server at mx1-lw-us.apache.org) with ESMTPS id E905D5F365 for ; Sat, 22 Oct 2016 00:08:39 +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 u9M08d1Y026351; Sat, 22 Oct 2016 00:08:39 GMT Message-Id: <201610220008.u9M08d1Y026351@ip-10-146-233-104.ec2.internal> Date: Sat, 22 Oct 2016 00:08:39 +0000 From: "Henry Robinson (Code Review)" To: impala-cr@cloudera.com, reviews@impala.incubator.apache.org CC: Matthew Jacobs , Alex Behm Reply-To: henry@cloudera.com X-Gerrit-MessageType: comment Subject: =?UTF-8?Q?=5BImpala-ASF-CR=5D_IMPALA-4335=3A_Don=27t_send_0-row_batches_to_sink=0A?= X-Gerrit-Change-Id: I7d339c1f9a55d9d75fb0e97d16b3176cc34f2171 X-Gerrit-ChangeURL: X-Gerrit-Commit: f7847122f5dc335982e107c9ab8c4d83e8a1d44a 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/2.12.2 archived-at: Sat, 22 Oct 2016 00:08:44 -0000 Henry Robinson has posted comments on this change. Change subject: IMPALA-4335: Don't send 0-row batches to sink ...................................................................... Patch Set 2: (1 comment) http://gerrit.cloudera.org:8080/#/c/4787/2/be/src/exec/plan-root-sink.cc File be/src/exec/plan-root-sink.cc: Line 88: // Don't enter the loop if batch->num_rows() == 0; no point triggering the consumer with > This sounds rather benign. Mention that some clients may not handle empty b It's benign, but it's true: we don't want to trigger the consumer (why pay a context switch to do no work and force another RPC?). -- To view, visit http://gerrit.cloudera.org:8080/4787 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I7d339c1f9a55d9d75fb0e97d16b3176cc34f2171 Gerrit-PatchSet: 2 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Henry Robinson Gerrit-Reviewer: Alex Behm Gerrit-Reviewer: Henry Robinson Gerrit-Reviewer: Matthew Jacobs Gerrit-HasComments: Yes