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 84DA510B35 for ; Wed, 9 Oct 2013 06:18:43 +0000 (UTC) Received: (qmail 5104 invoked by uid 500); 9 Oct 2013 06:18:43 -0000 Delivered-To: apmail-hbase-issues-archive@hbase.apache.org Received: (qmail 5025 invoked by uid 500); 9 Oct 2013 06:18:43 -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 4986 invoked by uid 99); 9 Oct 2013 06:18:42 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 09 Oct 2013 06:18:42 +0000 Date: Wed, 9 Oct 2013 06:18:42 +0000 (UTC) From: "Lars Hofhansl (JIRA)" To: issues@hbase.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (HBASE-9732) Static AtomicLong updated in StoreFileScanner every (re)seek 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-9732?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Lars Hofhansl updated HBASE-9732: --------------------------------- Attachment: 9732-trunk.txt And the trunk version. Note that seekCount in StoreFileScanner is no longer final, and it is also not declared as volatile (as that would again imply read/write barrier just to check whether the reference is null). It is up to the (single) test to do the right thing. I cannot stress enough how bad this is. All StoreFileScanners running inside a RegionServer content for this one AtomicLong on each seeks just for this this test. Running 3 client that all filter all rows with a RowFilter (which does a seek to the next row) gives a 10% improvement with this simple patch. > Static AtomicLong updated in StoreFileScanner every (re)seek > ------------------------------------------------------------ > > Key: HBASE-9732 > URL: https://issues.apache.org/jira/browse/HBASE-9732 > Project: HBase > Issue Type: Bug > Reporter: Lars Hofhansl > Fix For: 0.98.0, 0.94.13, 0.96.1 > > Attachments: 9732-0.94.txt, 9732-trunk.txt > > > To verify a single test case, we update a static AtomicLong for *every* seek performed on a RegionServer. This is especially bad with multiple seeks going on at the same time. > W.T.F...? > This penalty should only be incured when we're actually testing and need to count the seeks. -- This message was sent by Atlassian JIRA (v6.1#6144)