Где узнать «system clock granularity»?

CLOCK_GETRES(2)
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int clock_getres(clockid_t clk_id, struct timespec *res);
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DESCRIPTION
       The  function  clock_getres()  finds  the resolution (precision) of the
       specified clock clk_id, and, if res  is  non-NULL,  stores  it  in  the
       struct timespec pointed to by res.  The resolution of clocks depends on
       the implementation and cannot be configured by  a  particular  process.
       If  the  time value pointed to by the argument tp of clock_settime() is
       not a multiple of res, then it is truncated to a multiple of res.

SYSCONF(3)                 Linux Programmer's Manual                SYSCONF(3)

NAME
       sysconf - get configuration information at run time
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clock ticks - _SC_CLK_TCK
              The number of clock ticks per second.  The  corresponding  vari‐
              able  is obsolete.  It was of course called CLK_TCK.  (Note: the
              macro CLOCKS_PER_SEC does not give information:  it  must  equal
              1000000.)
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