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Real-life optimization work

Posted Nov 3, 2005 19:05 UTC (Thu) by dann (guest, #11621)
In reply to: Real-life optimization work by stef70
Parent article: All hail the speed demons (O'Reillynet)

The crypto libraries are brought in because gnome-vfs is linked to them.
libgnomeui links to gnome-vfs, so any GNOME application that links to libgnomeui will be linked to the crypto libraries.
It would be better if gnome-vfs dlopened the crypto libraries on demand when they are used, that would avoid linking all the GNOME applications to the crypto libraries (and probably avoid loading them from disk on startup, as they probably are not used).

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Posted Nov 4, 2005 13:26 UTC (Fri) by nix (subscriber, #2304) [Link]

Shared libraries are paged in, not `loaded from disk'; the overhead of using extra shared libraries on a prelinked system is very low indeed. (dlopen()ing is rather a lot more expensive, as you can't prelink dlopen()ed libraries.)

Real-life optimization work

Posted Nov 4, 2005 16:29 UTC (Fri) by dann (guest, #11621) [Link]

"Paging in" does not make a big difference for small libraries during a cold startup, at least the symbol table and the _init need to be read from the
disk. Extra disk seeks are expensive.

Real-life optimization work

Posted Nov 4, 2005 18:31 UTC (Fri) by oak (subscriber, #2786) [Link]

Only if your mass storage is slow at seeking.

This is not the case if you use instead of hard disk for example Flash memory like is done on many embedded devices.