Re: bcopy and page faults

From: Horst von Brand
Date: Fri Dec 17 2004 - 08:55:20 EST

firnnauriel <rinoa012000@xxxxxxxxx> said:
> In general, is there a correlation between the number
> of page faults occurred in the system and bcopy's
> performance?


> If the page fault is high, will the
> bcopy's performance become slower? Kindly enlighten me
> on this. If you can provide a URL that will support
> your answer, I will really appreciate it. Thank you
> very much!

bcopy(3) copies stuff inside a process. If the memory areas copied from/to
are available in RAM, the copy will go at full speed. If not, there will be
delays (due to paging, etc). Now, the system might be paging like mad, but
the memory _this_ process requires is available (== full speed bcopy), or
there might be almost no paging activity, but the pages required for the
copy aren't in RAM (== slowest possible).

PS: Consider using memcpy(3), bcopy is non-standard.
Dr. Horst H. von Brand User #22616
Departamento de Informatica Fono: +56 32 654431
Universidad Tecnica Federico Santa Maria +56 32 654239
Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513
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