개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

pcsample(2)

pcsample(2)                      System Calls                      pcsample(2)

NAME
       pcsample - program execution time profile

SYNOPSIS
       #include <pcsample.h>

       long pcsample(uintptr_t samples[], long nsamples);

DESCRIPTION
       The  pcsample()  function  provides CPU-use statistics by profiling the
       amount of CPU time expended by a program.


       For profiling dynamically-linked programs and 64-bit  programs,  it  is
       superior  to the profil(2) function, which assumes that the entire pro‐
       gram is contained in a small, contiguous segment of the address  space,
       divides this segment into "bins", and on each clock tick increments the
       counter  in  the  bin  where  the  program is currently executing. With
       shared  libraries  creating  discontinuous  program   segments   spread
       throughout  the  address space, and with 64-bit address spaces so large
       that the size of "bins" would be measured in  megabytes,  the  profil()
       function is of limited value.


       The  pcsample() function is passed an array samples containing nsamples
       pointer-sized elements. During program execution,  the  kernel  samples
       the program counter of the process, storing unadulterated values in the
       array on each clock tick. The kernel stops writing to the array when it
       is  full,  which  occurs after nsamples / HZ seconds of process virtual
       time.   The   HZ   value   is   obtained   by   invoking    the    call
       sysconf(_SC_CLK_TCK). See sysconf(3C).


       The sampling can be stopped by a subsequent call to pcsample() with the
       nsamples  argument set to 0. Like profil(), sampling continues across a
       call to fork(2), but is disabled by a call to one of the exec family of
       functions (see exec(2)). It is also disabled if an update of  the  sam‐
       ples[] array causes a memory fault.

RETURN VALUES
       The  pcsample()  function always returns 0 the first time it is called.
       On subsequent calls, it returns the number of samples that were  stored
       during  the  previous invocation. If nsamples is invalid, it returns −1
       and sets errno to indicate the error.

ERRORS
       The pcsample() function will fail if:

       EINVAL    The value of nsamples is not valid.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:

       tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE  TYPEAT‐
       TRIBUTE  VALUE _ MT-LevelAsync-Signal-Safe _ Interface StabilityCommit‐
       ted


SEE ALSO
       exec(2), fork(2), profil(2), sysconf(3C), attributes(7)

Oracle Solaris 11.4               10 Mar 1998                      pcsample(2)