c++ - How to compile a program to make it capable to use >4GB memory on 32-bit Linux? -

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the whole code written in c, c++, , fortran. possible make use more 4gb memory. crashed when reaches 3gb memory.

if possible, how set compiling options (or configure flags)?

we can use gcc, g++, ...or intel compilers

our os: fedora 12 x32

cat /proc/cpuinfo flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm tpr_shadow vnmi flexpriority bogomips : 5319.72 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual

unfortunately hitting limit that

r> 2^32 [1] 4294967296

which 4 gb limit. cannot index beyond for single application, no matter os.

this 1 of reasons many of switched 64 bit versions of our oss. linux has supported since late 1990s. switch fc (or ubuntu or ...) in 64bit.

one possible alternative installing more ram (which linux handle) , segmenting task on several instances of application, running in parallel. may not worth trouble...


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