Return-Path: X-Original-To: apmail-hbase-issues-archive@www.apache.org Delivered-To: apmail-hbase-issues-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 3D517105D6 for ; Mon, 6 Jan 2014 22:43:54 +0000 (UTC) Received: (qmail 45745 invoked by uid 500); 6 Jan 2014 22:43:54 -0000 Delivered-To: apmail-hbase-issues-archive@hbase.apache.org Received: (qmail 45713 invoked by uid 500); 6 Jan 2014 22:43:53 -0000 Mailing-List: contact issues-help@hbase.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Delivered-To: mailing list issues@hbase.apache.org Received: (qmail 45704 invoked by uid 99); 6 Jan 2014 22:43:53 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 06 Jan 2014 22:43:53 +0000 Date: Mon, 6 Jan 2014 22:43:53 +0000 (UTC) From: "Sergey Shelukhin (JIRA)" To: issues@hbase.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (HBASE-10241) implement mvcc-consistent scanners (across recovery) 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/HBASE-10241?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13863546#comment-13863546 ] Sergey Shelukhin commented on HBASE-10241: ------------------------------------------ Subtask 2 is trivial; the reason it is not done is that it is being done elsewhere (see how it's resolved as dup), so since it's not blocking us here and now it doesn't make sense to do double work. I am not working on this jira right now (will get back to it hopefully and there's a patch out in client subtask), but the plan was that I will do 1 and 3, and then take 2 if the other JIRA that does 2 is not done by then. HBASE-8763 does not need to block this, it's probably bigger than this entire JIRA. If it's done before this due to delays, good, if not, also good :) > implement mvcc-consistent scanners (across recovery) > ---------------------------------------------------- > > Key: HBASE-10241 > URL: https://issues.apache.org/jira/browse/HBASE-10241 > Project: HBase > Issue Type: New Feature > Components: HFile, regionserver, Scanners > Affects Versions: 0.99.0 > Reporter: Sergey Shelukhin > Assignee: Sergey Shelukhin > Attachments: Consistent scanners.pdf > > > Scanners currently use mvcc for consistency. However, mvcc is lost on server restart, or even a region move. This JIRA is to enable the scanners to transfer mvcc (or seqId, or some other number, see HBASE-8763) between servers. First, client scanner needs to get and store the readpoint. Second, mvcc needs to be preserved in WAL. Third, the mvcc needs to be stored in store files per KV and discarded when not needed. -- This message was sent by Atlassian JIRA (v6.1.5#6160)