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 5B7AD10C26 for ; Wed, 30 Apr 2014 01:52:23 +0000 (UTC) Received: (qmail 27019 invoked by uid 500); 30 Apr 2014 01:52:21 -0000 Delivered-To: apmail-hbase-issues-archive@hbase.apache.org Received: (qmail 26945 invoked by uid 500); 30 Apr 2014 01:52:21 -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 26786 invoked by uid 99); 30 Apr 2014 01:52:19 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 30 Apr 2014 01:52:19 +0000 Date: Wed, 30 Apr 2014 01:52:19 +0000 (UTC) From: "Jeffrey Zhong (JIRA)" To: issues@hbase.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Assigned] (HBASE-8763) [BRAINSTORM] Combine MVCC and SeqId 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-8763?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Jeffrey Zhong reassigned HBASE-8763: ------------------------------------ Assignee: Jeffrey Zhong > [BRAINSTORM] Combine MVCC and SeqId > ----------------------------------- > > Key: HBASE-8763 > URL: https://issues.apache.org/jira/browse/HBASE-8763 > Project: HBase > Issue Type: Improvement > Components: regionserver > Reporter: Enis Soztutar > Assignee: Jeffrey Zhong > Priority: Critical > Attachments: hbase-8736-poc.patch, hbase-8763_wip1.patch > > > HBASE-8701 and a lot of recent issues include good discussions about mvcc + seqId semantics. It seems that having mvcc and the seqId complicates the comparator semantics a lot in regards to flush + WAL replay + compactions + delete markers and out of order puts. > Thinking more about it I don't think we need a MVCC write number which is different than the seqId. We can keep the MVCC semantics, read point and smallest read points intact, but combine mvcc write number and seqId. This will allow cleaner semantics + implementation + smaller data files. > We can do some brainstorming for 0.98. We still have to verify that this would be semantically correct, it should be so by my current understanding. -- This message was sent by Atlassian JIRA (v6.2#6252)