View Source disksup (os_mon v2.10)

A Disk Supervisor Process

disksup is a process which supervises the available disk space in the system. It is part of the OS_Mon application, see os_mon(6). 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. 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The alarms are cleared automatically when the alarm cause is no longer valid.

Configuration

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

  • disk_space_check_interval = ``t:time/0 - 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(4) for information about how to change the value of configuration parameters.

See Also

alarm_handler, os_mon(3)

Summary

Types

time()

Supported units

Functions

get_almost_full_threshold()

get_almost_full_threshold() -> Percent

get_check_interval()

get_check_interval() -> MS

get_disk_data()

get_disk_data() -> [DiskData]

get_disk_info()

get_disk_info() -> [DiskData]

get_disk_info(Path)

get_disk_info(Path) -> DiskData

set_almost_full_threshold(Float)

set_almost_full_threshold(Float) -> ok

set_check_interval(Value)

set_check_interval(Time) -> ok

Types

Link to this type

time()

View Source (not exported) 
-type time() :: pos_integer() | {TimeUnit :: erlang:time_unit(), Time :: pos_integer()}.

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/0 and Time is a positive integer. The time interval needs to be at least one millisecond long.

Functions

Link to this function

get_almost_full_threshold()

View Source 
-spec get_almost_full_threshold() -> Percent :: integer().

get_almost_full_threshold() -> Percent

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

Link to this function

get_check_interval()

View Source 
-spec get_check_interval() -> Milliseconds :: integer().

get_check_interval() -> MS

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

Link to this function

get_disk_data()

View Source 
-spec get_disk_data() -> [DiskData]
                 when
                     DiskData :: {Id, TotalKiB, Capacity},
                     Id :: string(),
                     TotalKiB :: integer(),
                     Capacity :: integer().

get_disk_data() -> [DiskData]

Returns the result of the latest disk check. Id is a string that identifies the disk or partition. TotalKiB is the total size of the disk or partition in kibibytes. 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.

Link to this function

get_disk_info()

View Source (since OTP 26.0) 
-spec get_disk_info() -> [DiskData]
                 when
                     DiskData :: {Id, TotalKiB, AvailableKiB, Capacity},
                     Id :: string(),
                     TotalKiB :: integer(),
                     AvailableKiB :: integer(),
                     Capacity :: integer().

get_disk_info() -> [DiskData]

Immediately fetches total space, available space and capacity for local disks. Id is a string that identifies the disk or partition. TotalKiB is the total size of the disk or partition in kibibytes. AvailableKiB is the disk space used in kibibytes. Capacity is the percentage of disk space used.

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

Link to this function

get_disk_info(Path)

View Source (since OTP 26.0) 
-spec get_disk_info(Path :: string()) -> [DiskData]
                 when
                     DiskData :: {Id, TotalKiB, AvailableKiB, Capacity},
                     Id :: string(),
                     TotalKiB :: integer(),
                     AvailableKiB :: integer(),
                     Capacity :: integer().

get_disk_info(Path) -> DiskData

Immediately fetches total space, available space and capacity for a path. Id is a string that identifies the disk or partition. TotalKiB is the total size of the disk or partition in kibibytes. AvailableKiB is the disk space used in kibibytes. Capacity is the percentage of disk space used.

Returns [{Path,0,0,0}] if the Path is invalid or space can't be determined. Returns [{"none",0,0,0}] if disksup is not available.

Link to this function

set_almost_full_threshold(Float)

View Source 
-spec set_almost_full_threshold(Float :: float()) -> ok.

set_almost_full_threshold(Float) -> ok

Changes the threshold, given as a float (0.0 =< Float =< 1.0), 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.

Link to this function

set_check_interval(Value)

View Source 
-spec set_check_interval(time()) -> ok.

set_check_interval(Time) -> ok

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.