X-Recipient: archive-cygwin AT delorie DOT com
DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:message-id:date:from:mime-version:to:subject
	:references:in-reply-to:content-type:content-transfer-encoding;
	 q=dns; s=default; b=tuhVhvPmP8busg7edLAHHDWASv1Vb4/jkrB5KgTUw7z
	Z0I7LMZCsGJz3vRSuLVBgwyupWJQcOaHmjEkgjAbcOia4RjJc7zMyQ1PCmDGiEVa
	5oVA9zKrCrjLigplm4W8bwj7gJgdgOPIr53nE7TOLqGcfiTudvs5zXX2g69WXmtA
	=
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:message-id:date:from:mime-version:to:subject
	:references:in-reply-to:content-type:content-transfer-encoding;
	 s=default; bh=IlzFV/PT10KwfrGJ8J0UhWVdFms=; b=VYXxQaJokhR5RUeMu
	24l5pIMJEtV7qgza7Hns0iwdLuSIVkLx0kdufJPyMexcm1SXmvITbtrn7wGYtFsc
	ffvHr8z5KpOmuk7zfKYPXmjsEF3HnTilTgOgYAcfQKoSAG91cA1hQCtMTzDKzoLh
	ax0TCXK9uI/3DF+hlVbJSJbHTc=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.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
Authentication-Results: sourceware.org; auth=none
X-Virus-Found: No
X-Spam-SWARE-Status: No, score=-1.7 required=5.0 tests=AWL,BAYES_00,KHOP_THREADED,SPF_NEUTRAL autolearn=no version=3.3.2
X-HELO: out4-smtp.messagingengine.com
Message-ID: <521F699C.1060703@cwilson.fastmail.fm>
Date: Thu, 29 Aug 2013 11:32:44 -0400
From: Charles Wilson <cygwin AT cwilson DOT fastmail DOT fm>
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130801 Thunderbird/17.0.8
MIME-Version: 1.0
To: The Cygwin Mailing List <cygwin AT cygwin DOT com>
Subject: Re: xz -9 : Cannot allocate memory
References: <50A41697 DOT 3080406 AT tiscali DOT co DOT uk> <loom DOT 20130829T155739-66 AT post DOT gmane DOT org> <loom DOT 20130829T162752-851 AT post DOT gmane DOT org> <20130829151121 DOT GR21571 AT calimero DOT vinschen DOT de>
In-Reply-To: <20130829151121.GR21571@calimero.vinschen.de>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

On 8/29/2013 11:11 AM, Corinna Vinschen wrote:
> On Aug 29 14:34, Achim Gratz wrote:
>> Achim Gratz <Stromeko <at> NexGo.DE> writes:
>>> With the initial heap size set to 1MB, the same allocations for mmap work
>>> just fine.  The mmap length used by xz is the same for files of all sizes.
>>
>> The large mmap is for the scratchpad memory of xz, which can be limited via
>> the -M option.  Currently it fails when this gets larger than 616MiB
>> (standard for -9 is 674Mib).
>
> I'm not exactly surprised.  You're on a 32 bit machine, so you only have
> 2 Gigs VM.  Probably some DLLs are in the way.  Load xz under GDB, break
> on "cygwin_exit", run it, and when it hits the breakpoint, observer the
> memory layout, either in GDB, or by cat'ing /proc/<xz's pid>/maps.
> Observing the memory layout helps a lot to understand why there's some
> memory problem, especially if the application tries to get a big buffer
> space in a single chunk.

So...this is NOTABUG, right?  If you don't understand the options and 
their implications, and end up (as with -9) trying to allocate a giant 
hunk of memory unsupported by the memory model (e.g. 2GB VM), it fails. 
  I think that's preferable to falling back to -8 or -7 or something.

--
Chuck



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