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Date: Wed, 28 Feb 2001 13:53:20 -0500
From: Christopher Faylor <cgf AT redhat DOT com>
To: "'cygwin AT cygwin DOT com'" <cygwin AT cygwin DOT com>
Subject: Re: Memory problem
Message-ID: <20010228135320.E2327@redhat.com>
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References: <230667FC62B4D311BBA90050DA41CFD759D3D6 AT ddipdc DOT ddi DOT nl>
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In-Reply-To: <230667FC62B4D311BBA90050DA41CFD759D3D6@ddipdc.ddi.nl>; from p.boncz@datadistilleries.com on Wed, Feb 28, 2001 at 06:12:25PM +0100

On Wed, Feb 28, 2001 at 06:12:25PM +0100, Peter Boncz wrote:
>
>Christopher,
>
>My statement is about NT vs Unix, and has nothing to do with Cygwin (or its
>sbrk implementation).
>
>This is just me speaking out of experience with the exacltly the same
>(memory hungry) application on NT and on various Unixes. My experience is
>that the VirtualAlloc() implementation in NT is more prone to fragmentation
>on the long run than e.g. mmap() on Solaris and AIX. Just think that a
>request for a 450MB array can be impeded by just 4 small blocks of used
>virtual memory in awkward places. 

Mentioning VirtualAlloc in this context makes no sense.  The use of VirtualAlloc
is hidden from the user.  There have been posts here which mention how to
increase the size of Cygwin's heap which is a monotonic block of memory.

Search for the word "heap_chunk_in_mb" in the mailing list archives for
instructions on how to increase the heap size.

cgf

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