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.\" Copyright 2012 Cray Inc.
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.\" Licensed under LGPL 2.1 by Cray Inc.
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.TH LD.HUGETLBFS 1 "March 12, 2012"
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.SH NAME
ld.hugetlbfs \- link a program for huge pages
.SH SYNOPSIS
.B ld.hugetlbfs [options]
.SH DESCRIPTION

\fBld.hugetlbfs\fP replaces the normal \fBld\fP command for linking programs
to use hugepages.  Under gcc, you should use the option
\fB-B /usr/share/libhugetlbfs\fP which tells gcc to look in a non-standard
location for the linker.  This could be set in the \fBCFLAGS\fP environment
variable.

.TP
.B -Wl,--hugetlbfs-align

This method of linking an application permits greater flexibility at runtime.
Using HUGETLB_ELFMAP, it is possible to control which program segments are
placed in hugepages.  The following four settings will cause the indicated
segments to be placed in hugepages:

        HUGETLB_ELFMAP=R        Read-only segments (text)
        HUGETLB_ELFMAP=W        Writable segments (data/BSS)
        HUGETLB_ELFMAP=RW       All segments (text/data/BSS)
        HUGETLB_ELFMAP=no       No segments

It is possible to select specific huge page sizes for read-only and writable
segments by using the following advanced syntax:

        HUGETLB_ELFMAP=[R[=<pagesize>]:[W[=<pagesize>]]

.B -Wl,--hugetlbfs-link=B

Under binutils 2.16 or older, this option will link the application to store
BSS data (only) into hugepages.

.B -Wl,--hugetlbfs-link=BDT

Under binutils 2.16 or older, this option will link the application to store
text, initialized data and BSS data into hugepages.

.SH FILES
[DESTDIR|/usr/share]/doc/libhugetlbfs/HOWTO

.SH SEE ALSO
.I libhugetlbfs(7),
.I hugectl(8),
.I hugeedit(8)
.br
.SH AUTHORS
libhugetlbfs was written by various people on the libhugetlbfs-devel
mailing list.