prelink
1,improve the starting up speed of and exe.
2, normal process of starting up is
loading library->link lirary->excute the code (main)
3, Afer prelinking
loading library -> excute the code
4, prelink is and programe whose input is the exe.
1,in order for prelink to be useful, you need to have all your libraries compiled with fPIC, and be running glibc 2.3.1 or higher
2, can cause large performance boosts. It avoids a lot of calls to mmap that have to be done in the dynamic linking process.
3,prelink is a program which modifies ELF shared libraries and ELF dynam-
ically linked binaries
4, stores the relocations into the ELF object.
prelink first collects ELF binaries which should be prelinked and all
the ELF shared libraries they depend on. Then it assigns a unique vir-
tual address space slot for each library and relinks the shared library
to that base address. When the dynamic linker attempts to load such a
library, unless that virtual address space slot is already occupied, it
will map it into the given slot. After this is done, prelink with the
help of dynamic linker resolves all relocations in the binary or
library against its dependant libraries and stores the relocations into
the ELF object. It also stores a list of all dependant libraries
together with their checksums into the binary or library. For bina-
ries, it also computes a list of conflicts (relocations which resolve
differently in the binary’s symbol search scope than in the smaller
search scope in which the dependant library was resolved) and stores it
into a special ELF section.
At runtime, the dynamic linker first checks whether all dependant
libraries were successfully mapped into their designated address space
slots and whether they have not changed since the prelinking was done.
If all checks are successful, the dynamic linker just replays the list
of conflicts (which is usually significantly shorter than total number
of relocations) instead of relocating each library.
ELF Prelinking
http://www.crast.us/james/articles/prelink.php
Prelink
http://www.linuxcommand.org/man_pages/prelink8.html
Gentoo Linux Prelink Guide
http://www.gentoo.org/doc/en/prelink-howto.xml
编译ARM版Prelink（absurd）
http://blog.csdn.net/absurd/archive/2007/04/10/1559598.aspx