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    SubjectRe: HZ, preferably as small as possible
    Użytkownik Bill Davidsen napisał:
    > On Thu, 11 Jul 2002, Martin Dalecki wrote:
    >
    >
    >>vmstat.c:
    >>
    >>hz = sysconf(_SC_CLK_TCK); /* get ticks/s from system */
    >>
    >>And yes I know the libproc is *evil* in this area.
    >>The rest should be an implementation detail of sysconf().
    >
    >
    > Yes, any of the changes need to make the dynamic value available to
    > programs. Alas, too many programs grab the HZ value and compile it in, and
    > don't work right on a kernel with a modified rate. I don't know if the
    > CLK_TCK macro is dynamic or not, I sure hope so.
    >
    > I'd like to see it set at boot time, and available in /proc/sys for easy
    > use by scripts. As noted by others, there are a lot of uses in the kernel
    > source which assume that arithmetic will happen at compile time, and even
    > if you ignore the overhead it would take a lot of rewriting to make it
    > dynamic. Setting it a boot time gets most of the gain and none of the
    > pain (boot time = pick a kernel, not a parameter).
    >

    IMHO there where reasons why the standards are defining a function
    to access this information from applications.

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