From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: bolega Newsgroups: gmane.emacs.help Subject: dd - unequal speed from partition to partition, partition to file, file to partition Date: Mon, 28 Mar 2011 12:28:03 -0700 (PDT) Organization: http://groups.google.com Message-ID: <25819901-c857-405d-8ef6-ee0ac2ee1ea0@18g2000prd.googlegroups.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: dough.gmane.org 1301341231 9385 80.91.229.12 (28 Mar 2011 19:40:31 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Mon, 28 Mar 2011 19:40:31 +0000 (UTC) Cc: gnuist006@gmail.com To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon Mar 28 21:40:27 2011 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Q4IIc-0006Gg-Te for geh-help-gnu-emacs@m.gmane.org; Mon, 28 Mar 2011 21:40:27 +0200 Original-Received: from localhost ([127.0.0.1]:50261 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q4IIa-0000gS-Us for geh-help-gnu-emacs@m.gmane.org; Mon, 28 Mar 2011 15:40:24 -0400 Original-Path: usenet.stanford.edu!postnews.google.com!18g2000prd.googlegroups.com!not-for-mail Original-Newsgroups: comp.os.linux.misc,comp.unix.shell,comp.lang.c,gnu.emacs.help Original-Lines: 25 Original-NNTP-Posting-Host: 75.31.68.83 Original-X-Trace: posting.google.com 1301340484 6669 127.0.0.1 (28 Mar 2011 19:28:04 GMT) Original-X-Complaints-To: groups-abuse@google.com Original-NNTP-Posting-Date: Mon, 28 Mar 2011 19:28:04 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: 18g2000prd.googlegroups.com; posting-host=75.31.68.83; posting-account=REkl4woAAABFXaU7nL79XtGpnmNCQ415 User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2) Gecko/20100115 Firefox/3.6,gzip(gfe) Original-Xref: usenet.stanford.edu comp.os.linux.misc:801752 comp.unix.shell:250063 comp.lang.c:994157 gnu.emacs.help:186362 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:80491 Archived-At: dd - unequal speed from partition to partition, partition to file, file to partition /dev/sda1 to /dev/sda2 around 25Meg/s /dev/sda1 to a file_sda1 around 12Meg/s file_sda1 to /dev/sda1 around 5Meg/s Why ??? I have played with various block sizes such 1M, 4M, 500M In the all three cases, its from the same disk to itself OR from different disks, eg SATA to USB ... if I recall correctly. Please give an explanation why read from a file to disk partition is so slow ??? Bolega