From: Raymond W. <ra...@li...> - 2004-05-21 02:21:06
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In Linux, the parameter setting of "bs=1 count=1024" takes longer than "bs=1024 count=1". -----Original Message----- From: use...@li... [mailto:use...@li...] On Behalf Of Anthony Brock Sent: Friday, May 21, 2004 5:56 AM To: use...@li... Subject: RE: [uml-user] Migrating uml image > -----Original Message----- > Ah !! BTW, anyone correct me if I'm wrong, but there is no need > to use params bs and count, > dd will work just fine until it encounters EOF, right ? Across a network connection it may not matter so much. But past experience has strongly recommended setting the 'bs' parameter to as large a value as possible that will still remain within available free memory. For example, a while back I was copying Solaris 9 HD images between physical drives (on the same machine). The first time I launched the command, I failed to specify the 'bs' parameter (default was 512 bytes). It was less than half completed 29 hours later. I was able to reduce the copy time to around 2 hours by changing the 'bs' parameter to 64M. However, I believe you're right concerning the EOF. The primary reason for count is when copying from /dev/zero (which will NEVER give an EOF) or special file manipulations. Tony ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ User-mode-linux-user mailing list Use...@li... https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.687 / Virus Database: 448 - Release Date: 16/5/2004 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.687 / Virus Database: 448 - Release Date: 16/5/2004 |