Date: Fri, 16 Nov 2007 14:47:26 +0100 From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no> To: freebsd-chat@FreeBSD.ORG Subject: Re: C out-of-bound pointer question Message-ID: <861waql2tt.fsf@ds4.des.no> In-Reply-To: <200711160756.lAG7uGA1017136@lurza.secnetix.de> (Oliver Fromme's message of "Fri\, 16 Nov 2007 08\:56\:16 %2B0100 \(CET\)") References: <200711160756.lAG7uGA1017136@lurza.secnetix.de>
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Oliver Fromme <olli@lurza.secnetix.de> writes: > It is true that the k[] array in v2.0 uses 1 GB of mapped memory, > *BUT* it does not use 1 GB of RAM. It only uses one page of physical > RAM. Remember that RAM is allocated dynamically when it is accessed > for the first time, so if you never access k[0..268435409], then no > RAM will be allocated for it. Of course, you should make sure that it > is a local variable (or a malloc()ed one) that is not initialized, or > otherwise the initialization will cause RAM to be allocated. Make > sure you initialize only the indices that you need. It can't be a local variable; it's larger than the stack. DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no
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