NAME

       disksup - A Disk Supervisor Process

DESCRIPTION

       disksup  is  a process which supervises the available disk space in the system. It is part
       of the OS_Mon application, see os_mon(7). Available for Unix and Windows.

       Periodically checks the disks. For each disk or partition which uses more than  a  certain
       amount of the available space, the alarm {{disk_almost_full, MountedOn}, []} is set.

         On Unix:
           All (locally) mounted disks are checked, including the swap disk if it is present.

         On WIN32:
           All logical drives of type "FIXED_DISK" are checked.

       Alarms  are  reported to the SASL alarm handler, see alarm_handler(3erl). To set an alarm,
       alarm_handler:set_alarm(Alarm) is called where Alarm is the alarm specified above.

       The alarms are cleared automatically when the alarm cause is no longer valid.

DATA TYPES

       time()

              Supported units:

                integer() >= 1:
                  The time interval in minutes.

                {TimeUnit, Time}:
                  The time interval Time in a time unit specified by TimeUnit where  TimeUnit  is
                  of  the  type  erlang:time_unit()  and  Time  is  a  positive integer. The time
                  interval needs to be at least one millisecond long.

CONFIGURATION

       The following configuration parameters can be used to change the default values  for  time
       interval and threshold:

         disk_space_check_interval = time():
           The time interval for the periodic disk space check. The default is 30 minutes.

         disk_almost_full_threshold = float():
           The  threshold,  as  percentage of total disk space, for how much disk can be utilized
           before the disk_almost_full alarm is set. The default is 0.80 (80%).

         disksup_posix_only = bool():
           Specifies whether the disksup helper process should only use POSIX conformant commands
           (true)  or  not. The default is false. Setting this parameter to true can be necessary
           on embedded systems with stripped-down versions of Unix tools like  df.  The  returned
           disk data and alarms can be different when using this option.

           The  parameter  is  ignored  on  platforms  that  are known to not be POSIX compatible
           (Windows and SunOS).

       See config(5) for information about how to change the value of configuration parameters.

EXPORTS

       get_disk_data() -> [DiskData]

              Types:

                 DiskData = {Id, KByte, Capacity}
                  Id = string()
                  KByte = int()
                  Capacity = int()

              Returns the result of the latest disk check. Id is a  string  that  identifies  the
              disk  or  partition.  KByte  is  the total size of the disk or partition in kbytes.
              Capacity is the percentage of disk space used.

              The function is asynchronous in the sense that it does not invoke a disk check, but
              returns the latest available value.

              Returns [{"none",0,0}] if disksup is not available.

       get_check_interval() -> MS

              Types:

                 MS = int()

              Returns the time interval, in milliseconds, for the periodic disk space check.

       set_check_interval(Time) -> ok

              Types:

                 Time = time()

              Changes the time interval for the periodic disk space check.

              The  change  will  take  effect after the next disk space check and is non-persist.
              That is, in case of a process restart, this value  is  forgotten  and  the  default
              value will be used. See Configuration above.

       get_almost_full_threshold() -> Percent

              Types:

                 Percent = int()

              Returns the threshold, in percent, for disk space utilization.

       set_almost_full_threshold(Float) -> ok

              Types:

                 Float = float(), 0=<Float=<1

              Changes the threshold, given as a float, for disk space utilization.

              The  change  will  take effect during the next disk space check and is non-persist.
              That is, in case of a process restart, this value  is  forgotten  and  the  default
              value will be used. See Configuration above.

SEE ALSO

       alarm_handler(3erl), os_mon(3erl)