Return-Path: X-Original-To: apmail-hbase-user-archive@www.apache.org Delivered-To: apmail-hbase-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 6DEDA9959 for ; Mon, 3 Sep 2012 09:04:32 +0000 (UTC) Received: (qmail 16173 invoked by uid 500); 3 Sep 2012 09:04:30 -0000 Delivered-To: apmail-hbase-user-archive@hbase.apache.org Received: (qmail 15328 invoked by uid 500); 3 Sep 2012 09:04:23 -0000 Mailing-List: contact user-help@hbase.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hbase.apache.org Delivered-To: mailing list user@hbase.apache.org Received: (qmail 15300 invoked by uid 99); 3 Sep 2012 09:04:22 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 03 Sep 2012 09:04:22 +0000 X-ASF-Spam-Status: No, hits=1.8 required=5.0 tests=FREEMAIL_ENVFROM_END_DIGIT,FSL_RCVD_USER,HTML_MESSAGE,RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of liulei412@gmail.com designates 209.85.223.169 as permitted sender) Received: from [209.85.223.169] (HELO mail-ie0-f169.google.com) (209.85.223.169) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 03 Sep 2012 09:04:16 +0000 Received: by iec9 with SMTP id 9so4202283iec.14 for ; Mon, 03 Sep 2012 02:03:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=rNwVuvb9wAPR22RhIcX37A9LrSRuu6BD/t668XrsRqs=; b=wq3zbuyQShV1UIefTZF5jYWD3oYNf/lm2wm0f1qn0k82CbaBvlsLY4canu9t0Jf6P1 XIneKoNyIiDs5KuvzmiiuVh7XTQxEnvFVme2gYCGZdCs9wfyK+yChyBCTvmhBUIcvfq5 JVJE61CZv7ozO1jnZQUaRjRzs22DgHHOeYGOhyHoODWnjwytQsYJmdVVDBf2Rf6iGPt/ YxsFKiA3CHUxhgzhgkLojZKzb+ReEGOC/5XCnZCtRVe6dThXisaMpRWgkd6fmC2FMAf0 nsibTQ7PnlLVueu7OjTF3OhmPOYG+ych1D/NIZgC9nxRmo/4EIKpj17KZf/uv/EEvX+T ieRg== MIME-Version: 1.0 Received: by 10.42.180.201 with SMTP id bv9mr1761973icb.43.1346663035729; Mon, 03 Sep 2012 02:03:55 -0700 (PDT) Received: by 10.64.59.193 with HTTP; Mon, 3 Sep 2012 02:03:55 -0700 (PDT) Date: Mon, 3 Sep 2012 17:03:55 +0800 Message-ID: Subject: when all index block are in block cahe , the scan should use random-read From: jlei liu To: user@hbase.apache.org Content-Type: multipart/alternative; boundary=90e6ba6e8d68e0760504c8c86bbb X-Virus-Checked: Checked by ClamAV on apache.org --90e6ba6e8d68e0760504c8c86bbb Content-Type: text/plain; charset=ISO-8859-1 I am using the Hbase0.94 version. The scan use sequential read in Hbase0.94. if all index block of one HFile are in block cache , when user set start key and stop key, we can use *BlockIndexReader.seekToDataBlock(startKey) and BlockIndexReader.seekToDataBlock(**stopKey) to receive offsets of start data block and end data block, and then we can use the pread to implement scan, I think that can improve scan performance. * --90e6ba6e8d68e0760504c8c86bbb--