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Real-life optimization work

Posted Nov 4, 2005 13:26 UTC (Fri) by nix (subscriber, #2304)
In reply to: Real-life optimization work by dann
Parent article: All hail the speed demons (O'Reillynet)

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.)

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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 (guest, #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.