Return-Path: X-Original-To: apmail-cassandra-commits-archive@www.apache.org Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id B56301009D for ; Wed, 2 Apr 2014 22:59:21 +0000 (UTC) Received: (qmail 28714 invoked by uid 500); 2 Apr 2014 22:59:20 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 28553 invoked by uid 500); 2 Apr 2014 22:59:18 -0000 Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list commits@cassandra.apache.org Received: (qmail 28499 invoked by uid 99); 2 Apr 2014 22:59:17 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 02 Apr 2014 22:59:17 +0000 Date: Wed, 2 Apr 2014 22:59:17 +0000 (UTC) From: "Benedict (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (CASSANDRA-6933) Optimise Read Comparison Costs in collectTimeOrderedData MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CASSANDRA-6933?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13958295#comment-13958295 ] Benedict commented on CASSANDRA-6933: ------------------------------------- LGTM, assuming the only changes are in ABSC.SearchIter I'm not sure the assert i2 != 0 buys us anything, it's pretty much provable it cannot ever be 0 (we have complete control over its value here), and even if we get it wrong it doesn't really stop anything bad happening (if we've got that wrong, we can still get i2 < i, which is just as bad) > Optimise Read Comparison Costs in collectTimeOrderedData > -------------------------------------------------------- > > Key: CASSANDRA-6933 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6933 > Project: Cassandra > Issue Type: Improvement > Components: Core > Reporter: Benedict > Assignee: Benedict > Priority: Minor > Labels: performance > Fix For: 2.1 > > Attachments: 6933-v3.txt, 6933-v4.txt > > > Introduce a new SearchIterator construct, which can be obtained from a ColumnFamily, which permits efficiently iterating a subset of the cells in ascending order. Essentially, it saves the previously visited position and searches from there, but also tries to avoid searching the whole remaining space if possible. -- This message was sent by Atlassian JIRA (v6.2#6252)