sg_get_disk_io_stats_diff(3) [debian man page]

sg_get_disk_io_stats(3) 				     Library Functions Manual					   sg_get_disk_io_stats(3)

NAME

       sg_get_disk_io_stats, sg_get_disk_io_stats_diff - get disk io statistics

SYNOPSIS

       #include <statgrab.h>

       sg_disk_io_stats *sg_get_disk_io_stats(int *entries);

       sg_disk_io_stats *sg_get_disk_io_stats_diff(int *entries);

DESCRIPTION

       Both  calls  take  a  pointer to an int, entries, which is filled with the number of disks the machine has. This is needed to know how many
       sg_disk_io_stats structures have been returned. A pointer is returned to the first sg_disk_io_stats.

       sg_get_disk_io_stats returns the disk IO stored in the kernel which holds the amount of data transferred since bootup. On  some	platforms,
       such  as  Solaris 7, this value is stored in a 32bit int, so wraps around when it reaches 4GB. Other platforms, such as Solaris 8, hold the
       value in a 64bit int, which wraps somewhere near 17 million terabytes.

       sg_get_disk_io_stats_diff is the same as sg_get_disk_io_stats except it will return the difference since the last call. So, for instance  a
       call  to  sg_get_disk_io_stats_diff is made, and called again 5 seconds later. Over that time, 2000 bytes of traffic were written and 10000
       bytes read. write_bytes will store 2000 bytes, read_bytes will store 10000, and systime will  store  5.	 This  function  copes	with  wrap
       arounds by the O/S so should be seemless to use.

       On  Solaris  libstatgrab will attempt to get the cXtXdXsX representation for the disk_name string. If it fails it will use a name like sd0.
       On some systems programs calling libstatgrab will need elevated privileges to lookup some of the names. The  mappings  are  built  up  when
       sg_init is called.

RETURN VALUES

       All diskio statistics return a pointer to a structure of type sg_disk_io_stats.

       typedef struct{
	       char *disk_name;
	       long long read_bytes;
	       long long write_bytes;
	       time_t systime;
       }sg_disk_io_stats;

       disk_name
	      The name known to the operating system.  (eg. on linux it might be hda)

       read_bytes
	      The number of bytes the disk has read.

       write_bytes
	      The number of bytes the disk has written.

       systime
	      The time period over which read_bytes and write_bytes were transferred.

BUGS

       On  the very first call sg_get_disk_io_stats_diff will return the same as sg_get_disk_io_stats.	After the first call it will always return
       the difference.

       On operating systems that hold only 32bits of data there is a problem if the values wrap twice. For example, on Solaris 7 if 9GB is  trans-
       ferred and the operating system wraps at 4GB, the sg_get_disk_io_stats_diff function will return 5GB.

SEE ALSO

       statgrab(3)

WEBSITE

       http://www.i-scream.org/libstatgrab/

i-scream						   $Date: 2005/04/25 11:25:45 $ 				   sg_get_disk_io_stats(3)

Check Out this Related Man Page

sg_get_cpu_stats(3)					     Library Functions Manual					       sg_get_cpu_stats(3)

NAME

       sg_get_cpu_stats, sg_get_cpu_stats_diff, sg_get_cpu_percents - get cpu usage

SYNOPSIS

       #include <statgrab.h>

       sg_cpu_percents *sg_get_cpu_percents(void);

       sg_cpu_stats *sg_get_cpu_stats(void);

       sg_cpu_stats *sg_get_cpu_stats_diff(void);

DESCRIPTION

       sg_get_cpu_stats()  and	sg_get_cpu_stats_diff()  both  return  static pointers of type sg_cpu_stats.  sg_get_cpu_stats() returns the total
       amount of "ticks" the operating system has spent in each of the different states. sg_get_cpu_stats_diff() returns the difference in "ticks"
       for  each  of  the  states  since  last time sg_get_cpu_stats_diff() or sg_get_cpu_stats() was called. If it has never been called, it will
       return the result of sg_get_cpu_stats().

       The value stored (the "ticks") will vary between operating systems. For example Solaris has a total of 100 per second, while Linux has sub-
       stantially more. Also, different operating systems store different information - you won't find nice cpu on Solaris for example.

       Because of this, you will ideally always want to work on a scale against the total, or in percentages.

       sg_get_cpu_percents() returns a pointer to a static sg_cpu_percents. The function calls sg_get_cpu_stats_diff() and changes the values into
       percentages. If it has never been called before (and nor has sg_get_cpu_stats() or sg_get_cpu_stats_diff()), the returned percentages  will
       be the systems total ever since its uptime. (Unless the counters have cycled)

RETURN VALUES

       There are two structures returned by the CPU statistics functions.

       typedef struct{
	       long long user;
	       long long kernel;
	       long long idle;
	       long long iowait;
	       long long swap;
	       long long nice;
	       long long total;
	       time_t systime;
       }sg_cpu_stats;

       typedef struct{
	       float user;
	       float kernel;
	       float idle;
	       float iowait;
	       float swap;
	       float nice;
	       time_t time_taken;
       }sg_cpu_percents;

       user  kernel  idle  iowait  swap  nice
	      The different CPU states.

       systime	time_taken
	      The time taken in seconds since the last call of the function, or the system time.

SEE ALSO

       statgrab(3)

WEBSITE

       http://www.i-scream.org/libstatgrab/

i-scream						   $Date: 2005/04/25 11:25:45 $ 				       sg_get_cpu_stats(3)

Linux and UNIX Man Pages

sg_get_disk_io_stats_diff(3) [debian man page]

Check Out this Related Man Page