Return-Path: X-Original-To: apmail-lucene-java-user-archive@www.apache.org Delivered-To: apmail-lucene-java-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 5E6CF9D98 for ; Wed, 11 Jan 2012 20:22:30 +0000 (UTC) Received: (qmail 55622 invoked by uid 500); 11 Jan 2012 20:22:27 -0000 Delivered-To: apmail-lucene-java-user-archive@lucene.apache.org Received: (qmail 54724 invoked by uid 500); 11 Jan 2012 20:22:26 -0000 Mailing-List: contact java-user-help@lucene.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: java-user@lucene.apache.org Delivered-To: mailing list java-user@lucene.apache.org Received: (qmail 54716 invoked by uid 99); 11 Jan 2012 20:22:26 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 11 Jan 2012 20:22:26 +0000 X-ASF-Spam-Status: No, hits=-0.0 required=5.0 tests=RCVD_IN_DNSWL_LOW,SPF_NEUTRAL X-Spam-Check-By: apache.org Received-SPF: neutral (nike.apache.org: local policy) Received: from [74.125.82.48] (HELO mail-ww0-f48.google.com) (74.125.82.48) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 11 Jan 2012 20:22:19 +0000 Received: by wgbds1 with SMTP id ds1so839412wgb.5 for ; Wed, 11 Jan 2012 12:21:59 -0800 (PST) Received: by 10.181.13.208 with SMTP id fa16mr1334073wid.12.1326313319232; Wed, 11 Jan 2012 12:21:59 -0800 (PST) MIME-Version: 1.0 Received: by 10.216.155.6 with HTTP; Wed, 11 Jan 2012 12:21:38 -0800 (PST) In-Reply-To: References: From: Michael McCandless Date: Wed, 11 Jan 2012 15:21:38 -0500 Message-ID: Subject: Re: Seem contradictive -- indexwriter in handling multiple threads To: java-user@lucene.apache.org Content-Type: text/plain; charset=ISO-8859-1 X-Virus-Checked: Checked by ClamAV on apache.org Yes that would work fine.... but you should see a net perf loss by doing so (once you include time to flush/sync the RAMDir to an FSDir). If you see a perf gain then please report back! Mike McCandless http://blog.mikemccandless.com On Wed, Jan 11, 2012 at 3:09 PM, Cheng wrote: > Can I create a RAMDirectory based writer and have it work cross all > threads? In the sense, I would like to use RAMDirectory every where and > have the RAMDirectory written to FSDirectory in the end. > > I suppose that should work, right? > > > On Wed, Jan 11, 2012 at 2:31 PM, Michael McCandless < > lucene@mikemccandless.com> wrote: > >> On Wed, Jan 11, 2012 at 1:32 PM, dyzc2010 wrote: >> >> > Mike, do you mean if I create a FSDirectory based writer in first place, >> then the writer should be used in every thread rather than create a new >> RAMDirectory based writer in that thread? >> >> Right. >> >> > What about I do want to use RAMDirectory to speed up the index and >> search processes? >> >> IndexWriter is very efficient in using RAM across multiple threads >> now... so this isn't worth it at indexing time. >> >> At search time... MMapDirectory is a good way to let the OS use >> currently free RAM for caching. >> >> Mike McCandless >> >> http://blog.mikemccandless.com >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org >> For additional commands, e-mail: java-user-help@lucene.apache.org >> >> --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org For additional commands, e-mail: java-user-help@lucene.apache.org