On Tue, 02 Apr 2013 16:50:33 -0700
John Reiser <jreiser(a)bitwagon.com> wrote:
> It does rather seem like we should consider just killing it
> [prelink], at least by default.
Prelinking shortens the time between execve() and first useful output.
A prelinked module reduces time spent in ld-linux, and increases
sharing of pages (which reduces time spent in kernel duplicating
copy-on-write pages.) The savings are *visible* when invoking an
interactive GUI program that has dozens of shared libraries, or when
several hundred smaller executables are invoked each second, such as
some 'make' clouds, etc.
I'm not so sure they are... perhaps it's time for another round of 'how
fast does libreoffice start when prelinked vs not' ?
Some systems want those savings, and are willing to pay with
slightly
less protection via reduced ASLR. Some administrators compensate
by running a full prelink daily, and a partial prelink of "hot"
modules (glibc, ...) a few times during the day, even as often as
hourly; and with parameters to reduce interference with modules which
are not being [re-]prelinked during the current run.
Indeed. Also, some administrators remove prelink and do not use it on
any of there systems. (Like say, Fedora Infrastructure, or all my home
machines).
kevin