X-Spam-Check-By: sourceware.org
Date: Thu, 9 Nov 2006 12:00:13 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: cyg mem limit or network failure? Other? dd(dsk->net).blksz>=64M:  Fail
Message-ID: <20061109110013.GD18141@calimero.vinschen.de>
Reply-To: cygwin AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
References: <4552ED55 DOT 7030007 AT tlinx DOT org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <4552ED55.7030007@tlinx.org>
User-Agent: Mutt/1.4.2i
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
Precedence: bulk
List-Unsubscribe: <mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

On Nov  9 00:56, Linda Walsh wrote:
> I was running some network bandwidth tests using "dd" (WinXP2/Cygwin)
> 
> I was timing copies of a 300MB file from local disk to a remote
> server.  The local computer has enough memory to hold the file
> in the memory cache once it is loaded.
> 
> I ran through increasing power-of-two block sizes from
> 512 bytes up to 512MB, where it, theoretically could read
> and write the file in one read and write for the whole file.
> Essentially (say "s:" is a network drive):
> 
> for (i = 512;  i<=512MB;  i = i*2) do {
>    dd  bs=$i  if=/tmp/input  of=/s/Video/output.dat
> }
> 
> Unfortunately, the test /fails/ at or above 64MB (actually at or
> above 65,005KB).  The ERROR message is:
> 
> dd: writing '/s/Video/output.dat': Resource temporarily unavailable

I tried this with a 120 Megs and 1.2 Gigs file and dd works with all
blocksize up to the tested 512 Megs for me.

Could this be a network issue with big blocksizes, maybe?


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/