From owner-freebsd-questions@FreeBSD.ORG Wed Apr 8 20:03:52 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A5BA4106567A for ; Wed, 8 Apr 2009 20:03:52 +0000 (UTC) (envelope-from emailrob@emailrob.com) Received: from mx02.dls.net (mx02.dls.net [216.145.245.198]) by mx1.freebsd.org (Postfix) with ESMTP id 85DF48FC22 for ; Wed, 8 Apr 2009 20:03:52 +0000 (UTC) (envelope-from emailrob@emailrob.com) Received: from [216.145.235.1] (helo=emailrob.com) by mx02.dls.net with esmtp (Exim 4.69) (envelope-from ) id 1LrcyD-0008Dz-Re; Wed, 08 Apr 2009 13:57:58 -0500 Message-ID: <49DCE5AD.70306@emailrob.com> Date: Wed, 08 Apr 2009 18:58:05 +0100 From: spellberg_robert User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.0.2) Gecko/20030208 Netscape/7.02 X-Accept-Language: en-us, en MIME-Version: 1.0 To: fbsd_questions Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Subject: [ fbsd_quest ] file_caching and hd caches X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Apr 2009 20:03:53 -0000 howdy, y'all --- so, i was looking over the offerings of the on_line retailing "usual suspects", when i got to thinking: q: to what extent does freebsd cache recently_used hard_drive files ? q: under freebsd, to what extent are hard_drive internal_caches and their sizes [ e. g., 2mb, 8mb, 16mb ] important ? i am not so much looking for a history_ and theory_of_operation as i am looking for a "yes/no" to the question: q: should i pay up for hd_cache, if the other hd parameters are the same ? something else that i just thought up while typing this: q: are hd internal_caches non_volatile ? id est, q: do the cache contents survive a power_cycle ? [ some supplementary "fyi"s: yes, i am aware that hd access_times are a relative "eternity" to a chip_set's hd_port. i am not thinking about ram_size and swap_size and "thrashing"; all of my boxen have plenty of ram. i know i have to read it in the first time. rather, i am thinking about opening and reading some file that i recently wrote and closed. ] in advance, i thank you. please cc. rob ps --- remember, slavery sucks; so, have a happy pesach.