Return-Path: Delivered-To: apmail-hbase-dev-archive@www.apache.org Received: (qmail 13878 invoked from network); 15 Oct 2010 02:05:37 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 15 Oct 2010 02:05:37 -0000 Received: (qmail 65646 invoked by uid 500); 15 Oct 2010 02:05:36 -0000 Delivered-To: apmail-hbase-dev-archive@hbase.apache.org Received: (qmail 65607 invoked by uid 500); 15 Oct 2010 02:05:36 -0000 Mailing-List: contact dev-help@hbase.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@hbase.apache.org Delivered-To: mailing list dev@hbase.apache.org Received: (qmail 65599 invoked by uid 99); 15 Oct 2010 02:05:36 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 15 Oct 2010 02:05:36 +0000 X-ASF-Spam-Status: No, hits=2.2 required=10.0 tests=FREEMAIL_FROM,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of yuzhihong@gmail.com designates 209.85.216.169 as permitted sender) Received: from [209.85.216.169] (HELO mail-qy0-f169.google.com) (209.85.216.169) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 15 Oct 2010 02:05:28 +0000 Received: by qyk7 with SMTP id 7so947070qyk.14 for ; Thu, 14 Oct 2010 19:05:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=XN77aYdXrwncZ2xKciBhdWoe5zP9trnTOinoZYlWMWU=; b=kqNHD86SnUVp7/KIrOKDme443UWjXoEEu6GnPwdYDDWnSg1BtCyteuEgJeh9Ep4xJV r2v+qwacbKvbEGHYZFp3foSGGQYhBWtdugIvoOoBBnFFJunqZE74YXNl65vJn2wjKcQG NmnDNjeHZi/+OI3AMw/inRVMcbMrZp7yYMjH4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=BSkB8TXEmIjGPkQLRJko4IvdIZKruhO5bH09kJhtWXZcbFC3JjmtYsiSjuNdJuWxrl dnpevTkK8vfRG8CiaF/wgPf0rcyfSUuSH0KGZeQECUMIh5Im6VdbEiywLYCYHRJ5rrHf VhbSZBSYXv9R2a/AgEb0y0q6z7qry1DQdePgo= MIME-Version: 1.0 Received: by 10.229.222.1 with SMTP id ie1mr91436qcb.214.1287108307752; Thu, 14 Oct 2010 19:05:07 -0700 (PDT) Received: by 10.229.6.16 with HTTP; Thu, 14 Oct 2010 19:05:07 -0700 (PDT) In-Reply-To: References: Date: Thu, 14 Oct 2010 19:05:07 -0700 Message-ID: Subject: Re: HBaseAdmin.flush() From: Ted Yu To: dev@hbase.apache.org Content-Type: multipart/alternative; boundary=001636283ed678959704929e41e1 X-Virus-Checked: Checked by ClamAV on apache.org --001636283ed678959704929e41e1 Content-Type: text/plain; charset=ISO-8859-1 J-D: If you can briefly point out the code in 0.89 which makes using WAL more reliable, that would be great. Thanks On Thu, Oct 14, 2010 at 5:51 PM, Jean-Daniel Cryans wrote: > Even if HBaseAdmin.flush is made synchronous, that won't get you far > since it's still processed sequentially on the region servers. A > better well-known option is to set hbase.regionserver.hlog.blocksize > to a small number, and if you want high durability you could set that > to 1KB (basically rolling at every new insert). Since this is > incredibly inefficient, a more wide-spread number (and one we used > while we were on 0.20) is 2MB. Set it higher if you have a high insert > rate, or lower if you don't insert very often. > > J-D > > On Thu, Oct 14, 2010 at 8:36 PM, Ted Yu wrote: > > We're still using 0.20.6 :-) > > > > On Thu, Oct 14, 2010 at 5:19 PM, Jean-Daniel Cryans >wrote: > > > >> If your Puts are using the WAL, and you are on 0.89, it's already as > >> durable as it can be without forcing flushes. > >> > >> J-D > >> > >> On Thu, Oct 14, 2010 at 8:07 PM, Ted Yu wrote: > >> > Hi, > >> > HBaseAdmin.flush() is asynchronous. > >> > In order to achieve high durability, do I have a better choice ? > >> > > >> > Thanks > >> > > >> > > > --001636283ed678959704929e41e1--